Manila: The military has beefed up security forces while observing a ceasefire agreement with a Muslim rebel group, following reports that a Filipino bomb expert, trained by Jemaah Islamiyah (JI), has been plotting attacks in the south, including test missions in Manila and nearby provinces, sources said.

Abdul Basit Usman, also known as Abu Ahmad, has successfully transferred the technology he learned from his JI mentors to some 20 followers who also belong to Muslim rebel groups in the south. "He is deadly in Mindanao. He could endanger Manila and nearby provinces for test missions that his followers were ordered to undertake," said a police officer.

There were also suspicions that Usman became part of Ameril Umbra Kato's forces, the Bangsamoro Islamic Freedom Fighter (BIFF), a breakaway Moro Islamic Liberation Front (MILF) group which has been engaged in peace talks with the government since 1997, said the officer.