Jakarta – A church in the eastern Indonesian city of Poso has been bombed and burnt to the ground, a policeman said on Tuesday, and an aid worker said the area was gripped with renewed religious tension.

The policeman in the Sulawesi island town, where hundreds of people died two years ago in clashes between Christians and Muslims, said the church was attacked early on Monday but there were no casualties.

"Based on our findings, the church was bombed and caught on fire," he told Reuters by telephone from Poso, some 1,670 km east of Jakarta. "But there were no clashes and the church was empty when the attack happened," the policeman said.

The bombing came amid renewed tension between Christians and Muslims in Poso following the arrival of Muslim paramilitaries called Laskar Jihad, said an aid worker who just returned from Poso to Jakarta.

He told Reuters that while the authorities subsequently imposed tighter security, the situation remained uneasy.

The same group has fought Christians in the Moluccas, not far from Poso, during three years of religious bloodshed which has claimed thousands of lives and forced tens of thousands to flee to neighbouring parts of Indonesia.

Communal conflict has plagued parts of Indonesia's outlying regions since the downfall of autocratic President Suharto in 1998. Earlier this year, hundreds of people, mostly settlers from Madura island, died in a fierce ethnic battle between the indigenous Dayaks and the Madurese in the vast island of Borneo.