In September and October 1945 a series of incidents took place involving pro-Dutch Eurasians, and atrocities were committed by Indonesian mobs against European internees. In late October and early November, the leadership of the mass Muslim organisations Nahdlatul Ulama and Masyumi declared that war in defence of the Indonesian motherland was Holy War, and thus an obligation for all Muslims. "Kyai" and their students began to stream into Surabaya from Islamic boarding schools throughout East Java. The charismatic Bung Tomo made use of local radio to encourage an atmosphere of fanatical revolutionary fervor across the city. Six thousand British Indian troops were sent into the city on 25 October to evacuate European internees and within three days fighting began. After heavy fighting between the British Indian forces and around 20,000 Indonesian armed regulars of the newly formed People's Security Army (TKR) and mobs of 70,000–140,000 people, the British flew in the influential President Sukarno, Vice-President Hatta and his ministers Amir Sjarifuddin, and a ceasefire was achieved on 30 October.