Jakarta – Twenty bodies were uncovered in two mass graves in Aceh province, police said yesterday, as President Megawati Sukarnoputri warned that a military offensive against rebels in the region may be extended.

National police spokesman Colonel Zainuri Lubis said the authorities were still examining the sites in the central Aceh villages of Guci and Krueng Pase and had been told by villagers that there may be as many as 300 bodies in the graves dating back to 1999.

"Therefore, the local security police are now searching for mass graves of the other 280 victims," he said, adding the 20 bodies were uncovered on Monday.

The announcement followed reports that soldiers in south-west Aceh had recovered two bodies from a grave at an abandoned Islamic boarding school.

The military launched a six-month offensive against separatist rebels in the province on May 19 after a ceasefire pact signed in December collapsed.

Ms Megawati said if the offensive failed to end the war, the campaign may be extended, Antara news agency reported. She reportedly made the comments while on a trip to Vietnam.