Tunisia’s presidency says four arrests have been made in connection with the attack as civil society groups call for silent demonstration on Thursday 
 
 More protests against the deadly attack at Tunisia’s Bardo national museum are planned for Thursday, as the prime minister said one of the two gunmen was known to security services. 
 
 The country is in shock after two Tunisian gunmen killed 18 tourists and three Tunisians on Wednesday in the deadliest attack on civilians in the country for 13 years. The gunmen were shot dead by security forces. 
 
 
 
 On Thursday afternoon security forces arrested four people in connection with the attack, Reuters reported the president’s office as saying. The army will also be deployed to increase security in Tunisia’s major cities. 
 
 In an interview with France’s RTL radio on Thursday morning, the prime minister, Habib Essid, said Tunisia was working with other countries to learn more about the attackers, identified as Yassine Laabidi and Hatem Khachnaoui. He said Laabidi had been flagged to intelligence, although not for “anything special”. 
 
 The night before, the newly elected president Beji Caid Essebsi gave an address to the nation in which he said: “I want the people of Tunisia to understand firstly and lastly that we are in a war with terror, and these savage minority groups will not frighten us. 
 
 
 
 “The fight against them will continue until they are exterminated.” 
 
 Authorities have launched a manhunt for two or three suspected accomplices in the attack. 
 
 Hours after the police ended the siege, thousands of Tunisians flocked to the capital’s main thoroughfare, Avenue Habib Bourguiba, waving red Tunisian flags and singing songs from the 2011 Arab spring revolution. 
 
 
 
 Mohammed Nasri, a young activist, said: “After the last election we thought we made a big step forward to real democracy, but what happened today was like a KO to our future. An attack so close to our parliament makes us speechless.” 
 
 Tunisia’s main trade union confederation and other civil society groups called for a silent demonstration later on Thursday outside the Bardo museum. The groups called on Tunisians to gather at 3pm GMT “to demonstrate our national unity in the fight against terrorism”. 
 
 Tunisia’s health minister, Said Aidi, said the number of dead had risen on Thursday to 23 people, including 18 foreign tourists, with almost 50 people wounded. Five Tunisians were killed, including two attackers. Aidi said all the injuries came from bullet wounds, and that several victims were brought in without identity documents. 
 
 As well as three Tunisian nationals, the gunmen killed four Italians, three Japanese, two Colombians, two Spaniards, an Australian, a Briton, a Pole and a French national. The nationalities of the other murdered tourists were not confirmed, but reports said an unknown number of South African tourists may have been involved. 
 
 
 
 Facebook Twitter Pinterest A woman holds a placard which reads ‘We are all Bardo’. Photograph: Chedly Ben Ibrahim/Demotix/Corbis 
 
 Spain’s foreign minister said two Spaniards who survived the attack hid inside the museum building all night. Jose Manuel Garcia-Margallo said Juan Carlos Sanchez and Cristina Rubio, who is four months pregnant, appeared after dawn on Thursday and were well. 
 
 The targeting of tourists by terrorists is a new phenomenon in Tunisia and a big blow to a country whose struggling post-revolution economy depends largely on its beach resorts and foreign visitors. Tunisia, which peacefully elected a new parliament in December, has prided itself as a model of political transition since the overthrow of the brutal authoritarian Zine al-Abidine Ben Ali in 2011, in contrast to the post-revolutionary difficulties of its troubled neighbours. 
 
 
 
 Facebook Twitter Pinterest Tunisian soldiers guarding the Bardo museum on Wednesday night. Photograph: Michel Euler/AP 
 
 But it has also been struggling to tackle the growing terrorist threat in the region and thousands of Tunisians have left to fight foreign jihad. The attack immediately raised questions about the Islamist terrorist threat to Tunisia amid mounting anxiety that jihadi violence is spilling over the border from neighbouring Libya, as well as Algeria. 
 
 Wednesday night’s protests took place close to the French embassy, which has been ringed by barbed wire and concrete barriers for many months, a sign of the apprehension the city feels about the threat of terrorist attack. 
 
 That threat has become real with the killings at the Bardo museum, in what is the first jihadi strike against civilians in Tunisia since its 2011 revolution; previously militants had restricted attacks to military and government targets. 
 
 “Today’s murderous assault targeted not only tourists and Tunisians but also the tolerant and rights-respecting society that Tunisians have been struggling to build,” said Eric Goldstein of Human Rights Watch. 
 
 The dilemma for many Tunisians now is how the government should respond: many are proud of their break from dictatorship, but worry about how the government can crack down on terrorism while preserving hard-won freedoms. 
 
 Tunisia's clear and present danger Read more 
 
 “Everybody is shocked,” said Houeida Anouar, of Huffington Post Maghreb. “The government now has a huge responsibility. I hated the state when you had no rights. I don’t want Tunisians to go there, it would be a horrible back-pedalling.” 
 
 The attack began just after midday as gunmen armed with Kalashnikovs opened fire in front of the Bardo museum, the country’s largest and an important tourist attraction, which houses one of the world’s biggest collections of Roman mosaics within a 19th-century palace adjacent to parliament. As the gunmen struck, tourists were getting out of coaches to visit the museum on a spring day that had seen scores of visitors, many from cruise ships docked in the port for the day. 
 
 Wafel Bouzi, a guide with a Spanish-speaking group, told journalists that on exiting the museum with his group, he saw in the car park “a young 25-year-old man, dressed normally, without a beard” who was holding a Kalashnikov. “I thought he was playing with it. Then he opened fire.” 
 
 'Our hearts are black': Tunisians in shock after gunmen target tourists in capital Read more 
 
 The gunmen began shooting near the coaches then entered the museum where hundreds of panicked visitors had taken refuge. Josep Lluís Cusidó, mayor of the small Catalan town of Vallmoll, was at the museum as part of a wedding anniversary trip with his wife. “A few men walked in and started shooting. We’re alive thanks to a miracle,” he told the Spanish news agency Efe. “These men suddenly started shooting and people started falling to the ground dead and things started falling from the ceiling … Everything happened so fast.” 
 
 Two Britons were “caught up in” the shootings, the British Foreign Office said, but did not specify whether they were among the dead or injured. 
 
 Wednesday’s attack was the worst since 2002, when an al-Qaida militant killed 21 people, mostly German tourists, after detonating a truck bomb in front of a historic synagogue on the Tunisian island of Djerba in 2002. 
 
 Facebook Twitter Pinterest Escorted by security forces, rescue workers bring a stretcher to the Bardo museum on Wednesday. Photograph: Salah Ben Mahmoud/AP 
 
 It came days after the death of Ahmed Al-Rouissi, a Tunisian also known as Abu Zakariya Al-Tunisi, who led a contingent of Islamic State fighters in Libya. He was killed in clashes with Libyan troops near the town of Sirte, a stronghold of followers of Muammar Gaddafi, the late Libyan strongman. 
 
 Tunisian commentators speculated there might be a connection between his death and Wednesday’s deadly attack. Pro-Isis Twitter accounts hailed the attack as “ghazwat Tunis” or the “raid of Tunis” (ghazwa is the description given to the early Islamic battles) and have cheered on the attackers. A purported Isis video from last December threatened attacks on Tunisia. 
 
 
 
 
 
 The Associated Press contributed to this report ||||| More than 40 people wounded in the attack 
 
 Tunisian authorities have arrested nine people allegedly linked to Wednesday's attack apparently targeting tourists at a museum in Tunis that killed at least 21 people and injured 47 others. 
 
 "Security forces were able to arrest four people directly linked to the [terrorist] operation and five suspected of having ties to the cell," the presidency said in a statement on Thursday. 
 
 The Islamic State of Iraq and the Levant group has reportedly released audio recordings claiming responsibility over the attack at the National Bardo Museum. 
 
 Earlier on Thursday, officials identified two of the gunmen as Yassine Laabidi and Hatem Khachnaoui, saying one of the assailants was known to the intelligence services. 
 
 It was not clear which of the two men was known to the intelligence service and no formal links to a particular armed group had been established. 
 
 In an interview with France's RTL radio, Prime Minister Habib Essid said Tunisia was working with other countries to learn more about the attackers. 
 
 
 
 Both men were killed by security services in a raid after they attacked the museum. 
 
 Details about the attackers' identity emerged as President Beij Caid Essebsi vowed to wage a "merciless war against terrorism" after the gunmen killed 19 foreign tourists and two Tunisians in a daylight attack. 
 
 As the international community denounced Wednesday's assault, Essebsi said Tunisia would fight "to our last breath". 
 
 "I want the Tunisian people to understand that we are in a war against terrorism and that these savage minorities do not frighten us," said Essebsi, who visited some of the dozens being treated for wounds in a Tunis hospital. 
 
 The gunmen opened fire on the tourists - including visitors from Japan, Italy, France, Australia, Colombia, Poland and Spain - as they got off a bus then chased them inside the museum, said Prime Minister Habib Essid. 
 
 A Spanish man and a pregnant Spanish woman, who survived the attack by hiding in the museum all night in fear, were retrieved safely on Thursday morning by security forces, Tunisia's Health Minister Said Aidi told The Associated Press news agency. 
 
 Spain's foreign minister said police searched all night for the pair, Juan Carlos Sanchez and Cristina Rubio. 
 
 ... We are in a war against terrorism ... these savage minorities do not frighten us. We will fight them without mercy to our last breath. Beij Caid Essebsi, President of Tunisia 
 
 A Japanese survivor described how she and her mother were shot in the hail of bullets. 
 
 "I was crouching down with my arms over my head, but I was shot in the ear, hand and neck," 35-year-old Noriko Yuki said from her hospital bed in comments aired by Japanese broadcaster NHK. 
 
 "My mother beside me was shot in the neck. Mother couldn't move by herself when the police came over," she added. 
 
 Among the dead were three Japanese, four Italians, two Colombians and one each from Australia, France, Poland and Spain, Essid announced on television, in what he said was a definitive toll. 
 
 However, differing figures were given by other governments and there was conflicting information over the breakdown, with some of the dead identified as joint nationals. 
 
 The nationality of a 16th victim was not given, while the identity of the final fatality had not yet been established. 
 
 The Colombian tourists were a mother and child visiting Tunisia on a family holiday, their government said. The father survived the attack. 
 
 A Tunisian bus driver and a policeman were also reported dead in the attack on the Bardo, famed for its collection of ancient artefacts. 
 
 Al Jazeera's Jacky Rowland, reporting from Tunis, said there was a large police presence on the streets of the capital. 
 
 "We understand from the interior ministry that there may be other attackers or accomplices. It is believed there could be as many as three gunmen still out there." 
 
 Global condemnation 
 
 The attack appeared to be the worst on foreigners in Tunisia since an al-Qaeda suicide bombing of a synagogue killed 14 Germans, two French and five Tunisians on the island of Djerba in 2002. 
 
 It sparked outrage, with hundreds of people gathering later in a major thoroughfare of the capital, singing the national anthem and shouting slogans against the attackers, labelling them terrorists. 
 
 The assault also drew strong condemnation from world leaders, who vowed support for Tunisia. 
 
 US Secretary of State John Kerry denounced the "wanton violence" while British Prime Minister David Cameron said he was "appalled" by the attack and French President Francois Hollande expressed "solidarity" with the country. 
 
 United Nations Secretary-General Ban Ki-moon slammed the "deplorable" and "heinous" act and conveyed his "deepest sympathies" to the families of the victims. 
 
 Meanwhile the UN Security Council stressed that "no terrorist attack can reverse the path of Tunisia towards democracy". 
 
 Tunisia has seen an upsurge in Islamist dissent since the 2011 revolution that ousted longtime strongman Zine El Abidine Ben Ali. 
 
 Dozens of police and military personnel have been killed or wounded in attacks blamed on armed groups. ||||| Media playback is unsupported on your device Media caption The BBC's James Reynolds: "Tunisia has managed to avoid the larger wars which have hit other Arab states, but this attack... reveals its vulnerability" 
 
 A gunman involved in the attack that killed 20 tourists at the Bardo museum in Tunis was known to the authorities, Tunisia's prime minister has said. 
 
 Habib Essid told RTL Radio that security services had flagged up Yassine Laabidi, but were not aware of "anything specific" or of any links to known militant groups. 
 
 A Tunisian police officer also died in Wednesday's attack. 
 
 Both gunmen were killed. A search is on for suspects linked to them. 
 
 Two or three accomplices are still at large, an interior ministry spokesman told AFP news agency. The spokesman said both attackers were "probably" Tunisian. The second gunman has been named as Hatem Khachnaoui. 
 
 The tourists killed in the attack include visitors from Japan, Italy, Colombia, Australia, France, the UK, Poland and Spain, officials said. 
 
 On Thursday, three people - two Spanish tourists and one Tunisian museum worker - were found at the museum after having hidden there overnight, police said. 
 
 Tunisia's Culture Minister, Latifa Lakhdar, told reporters that the museum will re-open to the public early next week. 
 
 Image copyright AFP Image caption The attack targeted one of the most popular tourist attractions in Tunis 
 
 Image copyright AFP Image caption Security services eventually took control of the museum 
 
 Officials say more than 40 people, including tourists and Tunisians, were injured. The gunmen were killed after holding tourists hostage for several hours at the museum. 
 
 Speaking after the attack on national TV, Tunisia's President Beji Caid Essebsi said the country would not be cowed by terror attacks. 
 
 "These monstrous minorities do not frighten us," he said. "We will resist them until the deepest end without mercy." 
 
 At the time of the attack, deputies in the neighbouring parliament building were discussing anti-terrorism legislation. 
 
 Sayida Ounissi, an MP, told BBC Radio Four's Today programme that the security services had said the gunmen had originally planned to attack parliament. 
 
 A statement released by a jihadist media outlet gave a similar account, saying the gunmen began killing tourists after being repelled by police at the parliament. The statement did not say which group carried out the attack. 
 
 Image copyright AP Image caption Protesters lit candles and prayed at the gate of the museum 
 
 Image copyright AP Image caption Security was stepped up across Tunis, including at the museum 
 
 Many Tunisians took to the streets of central Tunis to protest against the attack, waving flags and lighting candles outside the museum. 
 
 World leaders condemned the attack and expressed their support for Tunisia's counter-terrorism efforts. 
 
 The UN Security Council issued a statement saying no terrorist action could reverse Tunisia's path towards democracy. The statement offered condolences to those affected by the attack, and called for the perpetrators to be brought to justice. 
 
 Who were the victims? 
 
 According to Tunisian authorities, 23 people were killed - though it is not clear if totals provided by the authorities include the gunmen. Some of the countries involved have given different totals and not all the dead have been identified. The dead include: 
 
 At least three Tunisians, including a police officer involved in the security operation 
 
 Five Japanese were killed, according to Mr Essid - although Japan says it has only confirmed the deaths of three citizens 
 
 Four Italians 
 
 Two Colombians 
 
 Two Spaniards 
 
 One national each from the UK, Australia, France and Poland 
 
 The attack is a huge blow for Tunisia's tourism industry and its government, which only emerged at the end of a long political transition several months ago, the BBC's Arab affairs editor Sebastian Usher says. 
 
 Islamist militants have tried to derail the democratic transition, which, although fragile, remains the most positive result of the Arab Spring in the Middle East, our correspondent adds. 
 
 Tourism is a key sector of Tunisia's economy, with large numbers of Europeans visiting the country's resorts. 
 
 In 2002, 19 people, including 11 German tourists, were killed in a bomb blast at a synagogue in the resort of Djerba. Al-Qaeda said it had carried out that attack. 
 
 Concerns about security in Tunisia have increased in recent months as neighbouring Libya has become increasingly unstable. 
 
 A large number of Tunisians have also left to fight in Syria and Iraq, triggering worries that returning militants could carry out attacks at home. 
 
 The Bardo National Museum 
 
 Image copyright AFP Image caption The museum is a major attraction in Tunisia
– "We are in a war with terror, and these savage minority groups will not frighten us," Tunisia's President Beji Caid Essebsi vowed in the wake of a terrorist attack that has now killed 18 foreign tourists and three Tunisians, plus the two gunmen. "The fight against them will continue until they are exterminated," he said in a speech last night, per the Guardian. He promised that "democracy will win and it will survive" as large numbers of demonstrators gathered in Tunis to protest the attack, reports Reuters. Meanwhile, ISIS militants today claimed responsibility for the attack, reports the BBC. But in a bright spot, two Spanish tourists who hid in the museum all night have now been found safe; Juan Carlos Sanchez tells the AP that "we thought the terrorists were still outside. But it was simply the police who were searching for people." Cristina Rubio is four months pregnant; both are fine. In other developments: Prime Minister Habib Essi says one of the two gunmen, Yassine Laabidi, was known to authorities, but security services were unaware of links to militant groups, the BBC reports. Both gunmen were killed by security forces, and authorities say they're still hunting several accomplices. Tunisia has now detained a total of nine people. Officials say tourists from Japan, Italy, Colombia, Australia, France, Poland, and Spain were killed in the attack, according to the BBC. Poland, which has sent a plane with doctors to help treat the injured, says two of its citizens were killed, two are missing, and nine are among the 40 or so wounded, the AP reports. Tunisia, birthplace of the Arab Spring, is the "Arab world's most successful democracy," which may have made it more of a target, but there are fears the attack could lead to greater authoritarianism, reports the New York Times. ISIS supporters are praising the attack online, as per the Times. The Telegraph reports that Tunisian media are speculating that Ahmed al-Rouissi, the country's most-wanted terrorist, may be involved. The Tunisian government says he became a senior ISIS leader in Libya and was killed in fighting last weekend. Tunisian officials have speculated that the adjacent Parliament building may have been the attackers' initial target, and that they may have switched to the museum because it had less security, the New York Times reports.