Three Indonesian policemen were wounded in the latest skirmish with rebels despite a ceasefire agreement in Aceh province, police said.

Three Brimob paramilitary policemen were shot during an ambush by rebel members of the Free Aceh Movement (GAM) in the Ujong Blang beach area at Bireuen district on Friday, said Bireuen district police chief Commissioner Laksa Widyana. He said the police had gone to the area for sightseeing and "not to look for fights" with GAM.

A GAM representative in the Joint Security Committee (JSC), Amri bin Abdul Wahab, confirmed the incident but accused Brimobs patrolling the area of provoking the confrontation.

The JSC includes security forces, GAM and foreign security monitors representing the Henry Dunant Centre, a Geneva-based humanitarian organisation which brokered the December 9 peace deal.

Wahab said seven of his men were shopping in a market when the Brimobs suddenly came out of an unmarked vehicle and attacked them. He said his men did not immediately return fire but eventually retaliated after being cornered by the Brimobs.

"In a cornered position, the GAM rebels returned fire to defend themselves while running to the woods. We had no idea that there were Brimobs injured in the incident," Wahab said.

Under a demilitarisation phase which began on February 9, rebels are over the course of five months due to place their weapons at locations known only to themselves and to the Henry Dunant Centre. The military should relocate its forces and change its role from a strike force to a defensive one.

An estimated 10,000 people have been killed in the 26-year conflict in the province on the northern tip of Sumatra island. Violence has greatly diminished since the peace pact, which is the first to be monitored by foreign observers.