Abu Sayyaf suspected in Philippines bombing

There have been several incidents of violence in the southern Philippines in recent weeks

ZAMBOANGA, Philippines (CNN) -- The Philippine government says it believes the Abu Sayyaf Muslim militant group was behind Sunday's bombing of a food court in the port city of Zamboanga in which at least five people died.

Interior Secretary Joey Lina told Philippine television initial evidence showed the bomb was planted in retaliation for an intensification of the military offensive against the group.

"The Abu Sayyaf members are behind this bombing although we have not exactly pinpointed who," Lina told ABS-CBN television Monday morning.

No group has claimed responsibility for the attack which occurred at about 2000 local time.

Around 30 people were injured in the blast.

A second bomb was found and safely detonated, police said.

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Initial reports said that 10 people were killed, but that number has since been revised down.

Officials said that there was no evidence that a team of U.S. military advisers were targeted in the attack.

The advisers, in the Philippines to assist the military in their long running battle against the Abu Sayyaf, were staying in Zamboanga a few miles from the blast site.

Bomb attacks

There have been several bomb attacks in the city in recent weeks. On October 7, three homemade bombs exploded in quick succession causing only minor damage.

Authorities have blamed the Abu Sayyaf for the attacks, saying that the militant group was using them as diversions to the military's offensive.

The Abu Sayyaf -- who say they are fighting for a Muslim homeland in the Philippines -- have been holding a group of hostages, including an American couple, since May on the nearby island of Basilan.

The military has stepped up an offensive against the militants and has claimed a number of small victories in recent days.

"Maybe [the bomb was] an offshoot of our continued operations in Basilan and in Sulu. Two days ago we ... killed one of their commanders. Maybe, just maybe, this is their retaliatory acts," Colonel Frank Gudani, spokesman for the military's Southern Command, told local radio.

The United States has linked the Abu Sayyaf to Osama bin Laden, the main suspect in the September 11 terrorist attacks in New York and Washington.