Jakarta – Indonesian police have enough evidence to bring new charges against jailed militant cleric Abu Bakar Ba'asyir, who is scheduled to be released from prison next month, a senior intelligence official said on Friday.

Police recently discovered a letter signed by two senior militants of the al-Qaida-linked Southeast Asia terror network Jamaah Islamiyah that addresses Bashir as the network's "emir," or leader, the official told The Associated Press on condition that his name not be used.

"Police have confiscated a very important document that proves that Abu Bakar Ba'asyir is the true leader of Jamaah Islamiyah," he said. "It's enough evidence to give Bashir a new trial." Ba'asyir is set to be released April 30 after serving his 18-month sentence for immigration violations, according to his lawyers. But foreign governments, especially Australia and the US, claim he has no right to go free, and that his release could incite further violence. Jamaah Islamiyah was blamed for both the October 2002 nightclub bombings on the island of Bali that killed 202 people and the August 2003 bombing of the Jakarta Marriott that killed 12.

The intelligence official said the US and Australianambassadors met on Friday with Indonesia's security minister to request that the case against Ba'asyir be reopened in order to prevent his release.

Spokesmen at each embassy confirmed that the meeting took place but declined to provide details.