BBC News Online: World: Asia-Pacific

Abu Sayyaf blamed for bomb blast

The food court was busy as the bomb went off

Interior Secretary Joey Lina said on Filipino television that the Abu Sayyaf were behind the attack although he said police had yet to pinpoint the identity of the bombers.

The Abu Sayyaf says it is fighting for a Muslim homeland in the southern islands of the Philippines. It has carried out a campaign of kidnappings and currently is thought to hold an American couple and about 10 Filipinos hostage.

Sunday evening's explosion caught people gathered in the popular food plaza in the Zamboanga mall.

Police said a second bomb planted close by failed to go off.

Witnesses said they saw bloodied people lying on the ground after the blast, which shattered windows in a mall across the street. Shoppers stampeded out of the mall.

"There was this bag that suddenly went off and in the next second, everybody fell to the ground," said Julie Santos, an employee at one of the food shops in the court.

Retaliation or protest

The Philippine military has been conducting a fierce offensive against the rebels on the main southern island of Mindanao and two smaller islands of Basilan and Jolo. Reports say the Abu Sayyaf have been suffering heavy casualties.

An armed foces spokesman Colonel Frank Gudani said: "Maybe [the bomb was] an offshoot of our continued operations... Maybe, just maybe, this is their retaliatory acts."

The regional army commander said the blast in Zamboanga could have been intended as a gesture of protest against the presence in the city of a group of American military advisers.

Officials say the advisers are in the region to assess the needs of the Philippine armed forces in their efforts to rescue the Abu Sayyaf's hostages.

The United States also says the group has ties to Osama Bin Laden, the chief suspect in the 11 September terrorist attacks on New York and Washington.