ZAMBOANGA (Philippines), Feb 16: Suspected Muslim fighters bombed a market and threw a grenade into a cinema in the southern Philippines on Saturday, killing four civilians as the United States stepped up its military buildup.

Dozens of people were injured in the blasts.

Local officials said the Abu Sayyaf guerillas, believed to be linked to Osama bin Laden and the target of the six-month-long US-Philippine manoeuvres, could be responsible.

“Most probably...this is a political message,” a police intelligence official said.

At least four people were killed and about 50 wounded when two bombs, hidden in garbage cans, exploded in the market on the island of Jolo, about 150kms south of Zamboanga.

In Zamboanga itself, a grenade hurled from a cinema balcony into the crowd below injured four people.

“We heard an explosion inside (the cinema) and people came rushing out yelling. Then a woman coated with blood came to us and said ‘I’m wounded, I’m wounded’,” said Juvy Pestano, a security guard at the Mindpro shopping mall where the cinema multiplex was located.

At an air base six kilometres away, US special forces troops were landing at the start of their deployment, Washington’s biggest expansion of the “war against terror” after the campaign in Afghanistan.

The attacks would not alter the schedule for the US forces, military officials said.

“The exercises will push through,” said Colonel Roland Detabali, operations chief for the southern Philippine military command.

Residents in Jolo said a letter purportedly written by an Abu Sayyaf leader was distributed there this week warning of bombings and kidnappings if military operations against them continued.

The group, which Washington has linked to Osama bin Laden’s Al Qaeda network, is fighting for an independent Muslim homeland in the south of the mainly Catholic nation.

The Abu Sayyaf has bases in the interior hills of Muslim-majority Jolo and nearby Basilan. Zamboanga is a Christian-dominated city on the mainland only a short ferry ride away.

ABU SAYYAF NAMED: “Our intelligence report is that the Abu Sayyaf will conduct bombings and kidnappings in Zamboanga,” said a police official after the cinema hall blast.

Asked if that was linked to the deployment of the US troops, the official said it appeared to be part of a general plan to “destabilize the peace and order situation”.

In Jolo, a senior military officer said authorities were investigating two possible angles to the explosions at the sidewalk market.

“Nobody has claimed responsibility for this horror,” said an army colonel.

“It could be an act of retaliation by gangs operating extortion activities at public markets. The other possibility is it could be a diversionary attack of the Abu Sayyaf.”

US SOLDIERS: Hundreds of US troops are in Zamboanga and on Basilan for the exercises. They will be spearheaded by about 160 special forces men, who began arriving in the area on Friday. US military transport planes flew dozens of the special forces to Zamboanga after the cinema blast.

“Our presence here and our resolve speaks for itself,” a US official said at the Philippine army brigade headquarters, on the outskirts of Isabela, provincial capital of Basilan.

The US presence on Basilan “thus sends a strong message that ...the government of the United States is very serious with its efforts to rid the world of terrorism,” the official said.

At the Zamboanga cinema, movie-goers seemed unperturbed by the explosion. By the evening, the cinema had reopened and people were queueing up for the late show. Only a small gash in the floor showed where the grenade had landed.—Reuters