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By Manny Mogato
MANILA, May 29 (Reuters) - A bomb believed to have been set off by a mobile phone exploded outside an air base in southern Philippines on Thursday, killing three people and wounding 17, police and the military said.
The bomb exploded as people were waiting to board a military transport plane at Zamboanga air base, said city police chief Lurimel Detran.
Zamboanga is one of the biggest cities in Mindanao in the violence-wracked southern Philippines. There was no immediate claim for the attack, but suspicion was centred on the Abu Sayyaf, a group of Islamic radicals who operate from the islands of Jolo and Basilan, off Zamboanga.
"This is an act of terrorism," said Colonel Darwin Guerra, army commander in the city. "It’s a command detonated bomb. We recovered fragments of a cell phone in the area."
There was no damage to the air base, he said.
Most of the victims were relatives of soldiers who are entitled to travel on military transport. Three died while being treated at a military hospital while others, including some children, sustained minor injuries.
Police chief Detran said four aid workers and two staff members of the city’s congresswoman were among those wounded in the blast.
"I was thrown off a few metres from my desk by the blast," said Wella Quintinio, one of the injured on the staff of Congresswoman Maria Isabelle Climaco, adding she saw several bodies sprawled on the street.
"I felt the ground shake, then I heard people shouting and crying and everybody seemed to be running around."
Military and civilian flights share the single runway at Zamboanga, but the civilian terminal is at a distance of about 3 km (2 miles) from the military area.
The blast shattered glass panels and windows of a nearby two-storey building that housed an army-run bank, a congressman’s office and a U.S. Agency for International Development (USAID) branch in Zamboanga City.
All the victims were locals, police said. (Editing by Raju Gopalakrishnan and Sanjeev Miglani)