ZAMBOANGA, Philippines (AP) _ A powerful bomb tore through a food court Sunday, killing at least six people and injuring scores while U.S. military officers were in town to discuss helping the government fight Muslim rebels.
The Americans were unhurt in the early evening attack in this city in the restive southern Philippines, officials said. They were staying at a tightly guarded military camp a few miles from the site of the explosion, said Lt. Gen. Roy Cimatu, who heads the Philippine military's Southern Command.
There was no evidence the group of more than 20 Americans was targeted, but Cimatu said the bombing might have been a protest against their presence. There were no credible claims of responsibility for the attack.
Cimatu said among the suspects was the Abu Sayyaf, an extremist Muslim group the Philippine military is targeting in a major offensive focusing on nearby Basilan island.
The Philippine government suspects the Abu Sayyaf of carrying out other recent bombings in Zamboanga as a diversion from the military offensive across the straits on Basilan.
The U.S. officers were here for talks on how the United States can help the Philippine government fight the Abu Sayyaf. The United States says the group has ties to Osama bin Laden, the chief suspect in the Sept. 11 terrorist attacks on New York and Washington.
Military and police officials gave death tolls in Sunday's attack ranging from four to 11, and officials at hospitals and morgues confirmed at least six deaths.
Medical workers said at least 53 people were hospitalized after the blast, which happened about 8 p.m. at the crowded open-air plaza in Zamboanga, on Mindanao island 520 miles south of Manila. Police said a second bomb was found outside and safely detonated.
Witnesses at the food court 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 Junie Santos, an employee at one of the food shops in the court.
Police and anti-terrorist troops brought in bomb-sniffing dogs and cordoned off the area, choked by smoke and dust. Officials were checking hospitals in an effort to count casualties.
The U.S. military advisers have been arriving in Zamboanga in small groups since Thursday. On Sunday, they returned there for the night after being flown by helicopter to Basilan, where Abu Sayyaf guerrillas are holding several hostages, including an American couple.
The Americans met with Philippine generals, visited combat troops and flew over parts of the island. The fact-finding mission could lead to Philippine forces receiving training and weapons from the United States, said Philippine Brig. Gen. Glicerio Sua.
``They saw the rugged mountains and forest and the bad roads from the air and now better appreciate the difficulties our troops are encountering,'' Sua said.
He said there would be follow-up visits, and that the U.S. team was also interested in hearing the government's plans for rehabilitating war-ravaged areas.
Military officials have said the United States will not send troops to battle the Abu Sayyaf, and Philippine President Gloria Macapagal Arroyo reiterated Sunday that U.S. ground troops were out of the question.
In an interview with Associated Press Television News in Hong Kong, where she was attending an economic conference, Arroyo expressed confidence that the rebels would be defeated soon.
The Abu Sayyaf say they are fighting for Muslim independence in the southern Philippines; the government calls them bandits who kidnap for ransom.
The rebels are holding American missionaries Martin and Gracia Burnham of Wichita, Kan., and 10 Filipinos on Basilan. They claim they killed a third American, Guillermo Sobero of Corona, Calif.; his remains were found in a Basilan jungle this month.
The three Americans were kidnapped from a resort in May.