Indonesian police say the military has found the remains of 20 people buried in two mass graves in Aceh Province, where government troops and separatist rebels are locked in battle. The discovery comes as the government issues new rules to restrict foreign media coverage of the conflict.

Indonesian police say the military is investigating the discovery of two mass graves in Aceh containing the remains of 20 people.

While both government and rebel forces face accusations of extra-judicial killing, the police say this grave could date back to the late 1990s. Numerous burial sites are believed to dot the province, plagued by more than 25 years of conflict.

Indonesian political science professor Salim Said said if the graves are older, then the victims were probably killed by the Army during a previous offensive there. He says a brutal nine-year military action, known as Operation Dong, took place in Aceh under former dictator Suharto from 1989 to 1998. But if the graves are found to be more recent, Professor Said said, then GAM, the local rebel movement, could be to blame. "There is also a possibility that the mass graves they are talking about are the mass graves of the victims of GAM, but we aren't clear yet," he said.

GAM representatives, however, deny any involvement and say the bodies are recent victims of the military and pro-government militias.

Mr. Said said that scenario is not likely since government soldiers are under tight scrutiny. "The military were there only last month, and they are accompanied by journalists and many observers. So it very difficult to imagine that the military would repeat the things they did during "Dong" under Suharto," he said.

But the government is now rolling back monitoring by journalists, declaring Thursday that foreign reporters will be barred from rural parts of Aceh where fighting is taking place.

Indonesia recently detained an American journalist who had been reporting on the conflict from the rebel side. He has been charged with violating the terms of his journalist visa. On Thursday, authorities arrested a Japanese news photographer for allegedly violating the new decree.

Rights groups are protesting the tighter media rules, concerned that abuses could take place without oversight. Aceh rebels have been fighting for independence since 1976. A peace deal was signed in December but broke down last month leading to a resumption of fighting.