Raissa Robles in Manila and Vaudine England in Jakarta – About 600 Indonesian rebels have just finished training at a Muslim separatist camp in the southern Philippines, the Philippine military claimed yesterday.

Extremist Muslims have been rumoured by some Indonesian observers to be behind religious unrest which has erupted throughout the Indonesian archipelago since the downfall of former president Suharto last May.

The military chief of Philippine Muslim rebel group the Moro Islamic Liberation Front, Al Haj Murad, branded the leaked three-page military intelligence report "all lies and lies".

But claims of a connection between radical Muslim groups in Indonesia and their counterparts in the Philippines did not surprise experienced observers in Jakarta yesterday.

The leaked military intelligence report claimed "the military training is allegedly in preparation for their planned declaration of holy war or 'jihad' against the Indonesian Government, which they deem to be veering away from pure Islamic practices".

It identified the group as the underground Indonesian Islamic Liberation Front, headed by Muhammad Salib Sulayman.

Members of the group recently completed four months of guerilla warfare training inside the main separatist base, Camp Abubakar, in central Mindanao, it added. The whereabouts of the rebels was not made clear.

The military had raised an alarm over the proliferation of undocumented Indonesians on the southern island of Mindanao, which it estimated at more than 6,000. But the Bureau of Immigration and Deportation in Davao City had managed to count only 161.

Murad said his group had not trained any Indonesian fighters. "They have their own struggle," he said. "We are fighting our own fight, although we have one thing in common, that is to establish a real independent Islamic state."

A group with a similar name to that of the reported group has been discussed in military circles in Indonesia, but "only at the level of rumour", one source in Jakarta said yesterday. Few others have heard of the group mentioned as undergoing training in the southern Philippines.

But no one was surprised that such an armed group might exist. "There have been several reports of arms making their way from there to here, from Mindanao to Indonesia," a separate source said.