Security in and around the Philippine capital has been tightened amid reports that Muslim extremists are planning a bombing campaign against civilian targets, security officials said on Monday.
Two bomb makers from the Rajah Solaiman Movement, a group of Christian converts to Islam, were believed to be hiding on the outskirts of Manila and could be constructing bombs, said the city's military commander, Brigadier General Ben Dolorfino.
The two were taking orders from Abu Sayyaf, a Muslim extremist group with links to the Al-Qaeda terrorist network, said Dolorfino.
He said the military and police had stepped up intelligence gathering in a bid to counter the threat, adding that elite anti-terror forces were ready for deployment in the capital.
Defense Assistant Secretary Ricardo Blancaflor said in a separate interview the government was aware of Rajah Solaiman Movement's presence but "we don't have information on specific targets."
"We always presume the worst and we always prepare for the worst," Blancaflor said, adding that more checkpoints would be set up on roads and security would be tightened at malls and other public places.
The Rajah Solaiman Movement was trained in bomb making by the Abu Sayyaf and Jemaah Islamiyah (JI) extremist groups, according to security officials.
The group is believed to have helped Abu Sayyaf when it firebombed a passenger ferry in 2004 in Manila Bay, killing more than 100 in the Philippines' worst terrorist attack.
In the past week, cities in the southern Philippines have been hit by a rash of bomb attacks, believed to be the work of Abu Sayyaf members, possibly to divert attention away from the military's pursuit of JI and Abu Sayyaf rebels on Jolo Island.
Twelve people were killed and scores wounded in the bombings, the latest occurring Sunday at a police camp on Jolo island.
In addition to Abu Sayyaf rebels being hunted on Jolo island are JI members Dulmatin and Umar Patek, who helped carry out the the nightclub bombings in Bali, Indonesia, in 2002 that killed 202 people.