Jenny Grant, Jakarta – Muslim students demonstrated in Jakarta yesterday demanding a holy war against Christians in Ambon. About 2,000 students massed in a central square shouting "jihad" and accusing the military and Christians of ethnic cleansing in Ambon.

The calls came as the first elements of 3,200 troop reinforcements were deployed on the riot-scarred island and the provincial police chief was sacked.

Meanwhile, Indonesia's top human rights activist claimed Jakarta's policy of placing Muslims in top posts on the mainly Christian Maluku islands lay behind unrest which has seen more than 150 people killed since mid-January, 38 of them in the past week. The 300 troops deployed in Ambon yesterday were Marines, trained to cope in riot situations.

As they took to the devastated streets of the provincial capital, armed forces chief General Wiranto announced he had ordered the dismissal of the Maluku police chief, Colonel Karyono. He also said he was withdrawing a battalion of troops drawn from mainly Muslim South Sulawesi out of Ambon.

General Wiranto said he had instructed the new troops sent to Ambon to take "very firm and tough" action against anyone who "destroys, burns, or disturbs the peace, regardless of their background".

On Monday, four Muslims were shot dead outside a mosque in Ambon, reportedly by members of the security forces. General Wiranto promised "firm action" against those involved.

In Jakarta, demonstrator Muhammad Najib, of Bogor Agriculture Institute, said the military was too late and too savage in its response to the Ambon riots. "We urge the military leadership to solve this problem or we will travel to Ambon to solve it ourselves," Mr Najib said. Later 50 mainly Christian migrants from Maluku staged a peaceful demonstration urging the military to stay neutral.

A source at the Maluku provincial office in Ambon put the number of people who had fled the island since the violence broke out at 30,000, and said 13,676 had sought refuge at mosques, churches and military bases, most because their homes had been destroyed.

Marzuki Darusman, the head of the National Commission on Human Rights, said that Jakarta in 1997 had forced the appointment of Muslim Saleh Latuconsina as Maluku governor. The governorship had traditionally been given to a Christian.

He said that such moves, and the migration of large numbers of Muslims from South Sulawesi and Java, had led Maluku's Christians to feel their culture was under threat.