BEIRUT—Violence linked to the war in Syria crept closer to the Lebanese capital, as rockets struck a Beirut suburb dominated by Shiite militant group Hezbollah.

The Sunday morning rocket attacks, launched from within Lebanon, came a day after Hezbollah's leader issued his strongest declaration yet of the group's support for the embattled Syrian regime.

The attacks on the southern fringes of Beirut, which didn't claim any lives, were the first such strikes near the capital in the more than two years of a civil war in Syria that has sent artillery into Lebanese border areas and embroiled local factions in fighting in the north of Lebanon.

Lebanese Sunni gunmen in Tripoli, northern Lebanon, on Sunday. Syria's war has spanned the border between the two countries. Reuters

Fighting in the northern city of Tripoli between Lebanese Sunnis, who back Syrian rebels, and Lebanese Alawites, from the same sect as Syria's President Bashar al-Assad, has killed 30 people and injured more than 200 in the past eight days, a Lebanese security official said. It has been the fiercest and longest bout there between the longtime rivals in many years.

The weekend of worsening violence, Lebanese leaders said, shows how Syria's war has degenerated into an ideological battle between sects that has spanned the border between the two countries.

The hardening of sectarian lines in Syria and across the region has come to define the battle between the Shiite-linked, Alawite-led Syrian regime and the Sunni-led rebel insurgency, and has damped prospects for a peaceful political resolution to the conflict.

Hezbollah chief Hassan Nasrallah, whose fighters are backing Syrian government troops, on Saturday called Syria a new front in the Shiite party's war against Israel and the West. He also criticized the Lebanese government—in which his party is a dominant force—for being defenseless in the face of violence in the country and on its borders.

In his first explicit admission of Hezbollah's role in Syria, Mr. Nasrallah framed the fight as necessary for the survival of the alliance between Hezbollah, the Syrian regime, and regional Shiite superpower Iran.

"Syria is the backbone of the resistance," Mr. Nasrallah, referring to his party, said in a televised speech on Saturday. "The resistance cannot sit idly by, arms crossed, as its back is exposed or its support broken," he said, mocking Lebanon as "a state of sects and a state of regions."

In Damascus, supporters of President Assad cheered Mr. Nasrallah's comments, seeing them as the most direct pledge by the Hezbollah chief to defend and protect the Syrian president, his longtime ally. Newspaper front pages carried headlines from the speech.

The Syrian state-owned Tishreen newspaper on Sunday carried a bold front-page headline above a photograph of Mr. Nasrallah delivering his speech the previous day.

Meanwhile, Syrian opposition pages on Facebook and other social-media websites were awash with inflammatory comments about Mr. Nasrallah, Hezbollah and Shiites.

Pro-regime pages on the same websites praised Mr. Nasrallah and the foresight of the Syrian regime in nurturing Hezbollah for years in coordination with their mutual ally Iran. For Assad loyalists, Damascus's bet on Hezbollah is paying off now, as the regime is fighting for its survival.

An undated black-and-white photograph showing the Syrian regime's founder, the late Hafez al-Assad, seated on the floor in a meeting with Iran's current Supreme Leader Ayatollah Ali Khamenei was posted on many of these pages.

"Our enemies will kneel at your feet," read a caption next to a photograph of Mr. Nasrallah posted on a pro-regime Facebook page titled "Syrian Truth."

Damascus agreed "in principle" on Sunday to take part in an international conference in June in Geneva, led by Russia and the U.S., that aims to bring members of the Syrian regime together with the opposition. Syrian Foreign Minister Walid al-Moallem, speaking in Baghdad, said the government was ready to participate in the talks, but that no world power has the right to "decide Syria's future on behalf of the Syrian people."

"In all good faith, we think the international conference presents a suitable opportunity for a political solution for the crisis in Syria," Mr. Moallem said.

In Lebanon, four Syrian workers were injured Sunday morning when a rocket slammed into an open-air car showroom in a southern suburb of Beirut that is a Hezbollah stronghold. The rocket was one of three launched early that morning from an uninhabited area in the mountains east of Beirut, security officials at the scene said.

Lebanese soldiers investigate a damaged room where a rocket struck an apartment in a building in the Chiyah neighborhood Sunday. Associated Press

A second rocket hit a house in the Chiyah neighborhood, a short distance away, but didn't explode and no one at the home was injured, neighbors and security officials said. A third rocket also didn't explode; it wasn't clear where that rocket had struck.

Syria in the Spotlight


There was no immediate claim of responsibility for the attack. Security officials at the scene said it was likely linked to local tensions over the war in Syria. They said a range of actors could be responsible, including local Lebanese or Palestinian factions allied with the Syrian rebels.

Lebanon's state news agency said the rockets were 107-millimeter Grad rockets, a type of small rocket Lebanese officials said have been fired before from south Lebanon into Israel.

Lebanese officials sought to play down tensions after the strikes. "We are living in an unacceptable atmosphere, and hope that the events in Syria don't occur in Lebanon and more levelheaded minds prevail," Interior Minister Marwan Charbel told reporters at the scene. "Lebanon cannot handle this," he said.

Syrian dissidents and U.S. officials say Iran and Hezbollah have guided the Syrian government in surveillance, and later, counterinsurgency strategies, since the early months of the uprising in 2011. Hezbollah fighters joined the battle in Syria in earnest earlier this year, to defend Shiite-majority Syrian towns along the Lebanese border and to protect a Shiite shrine in Damascus.

The Hezbollah fighters have been locked in battle alongside Syrian troops for a week in the town of Qusayr, about 10 kilometers, or 6 miles, from the border with Lebanon. The border area around the town, a rebel stronghold, is a strategic land link for Hezbollah in Lebanon with its ally Iran, and a supply route between Hezbollah and the Syrian regime.

Speaking Saturday on the anniversary of Israel's withdrawal from south Lebanon in 2000, Mr. Nasrallah conceded that Hezbollah had become involved in Syria "in the last few months" to defend border towns against what he called Sunni extremists backed by Israel and the West. He said so many of the party's fighters have volunteered to join the battle, he has had to turn some away.

"Brother and sisters: If Syria falls into the hands of the U.S., Israel, takfiri [extremists], and the tools of America in the region that call themselves regional states," he said, "the resistance will be besieged and Israel will enter Lebanon."

The U.S., which supports the Syrian opposition, has warned of the risks of more spillover of the crisis into Lebanon. President Barack Obama has expressed concern to Lebanese President Michel Suleiman over Hezbollah's role in Syria. Mr. Suleiman, in turn, cautioned Hezbollah on Friday against acting against the interests of national security.

Mr. Nasrallah's defiant speech on Saturday underscored how Hezbollah has come to view the war in Syria as a threat to its own existence, a position he appeared to reiterate to his Shiite constituency.

His opponents in Lebanon's government, which is split between camps allied with and opposed to the Syrian regime immediately slammed it as defiant and dangerous. "Nasrallah is calling the entire Lebanese entity into question," said Mohamad Chatah, a former minister and adviser allied with the anti-Hezbollah, pro-Western opposition in Lebanon. "What we are seeing is almost unprecedented….It is the complete disregard of other Lebanese and the Lebanese state," Mr. Chatah told a local TV channel.

In the Shiite-majority neighborhoods around where the rockets struck Sunday, residents—largely Hezbollah supporters—backed the party chief's characterization of the war in Syria as a fight for survival. Many said they believed the rocket attacks had been planned or instigated by Israel, the U.S. and their local Lebanese proxies in an attempt to provoke Hezbollah into a war on its own territory.

Many of the residents said they weren't interested in war, but wouldn't stay on the sidelines if they were further provoked.

"We have Seyed Hassan Nasrallah, God protect his life, behind us, and we are not afraid of those people, that trash," said Zuhair Sweid, the chief security guard for the car showroom where one of the rockets struck. "This is a cowardly act, a terrorist act, an Israeli act," Mr. Sweid said of the rocket attacks, adding: "Tell America to stop funding the terrorists."

"We, Lebanese, we are ready, if they want to come here," he said defiantly of his opponents, whom he described as a mix of Sunni jihadists from Syria and other countries, and Israelis. "Let them come down here."

—Sam Dagher in Damascus contributed to this article.

Write to Nour Malas at

Corrections & Amplifications
Hezbollah has openly backed Syrian government troops against rebels in a fight for strategic territory in the Syrian town of Qusayr. An earlier version of the article incorrectly stated that Hezbollah has backed the rebels.