MANILA (AP) — A powerful blast from a suspected bomb ripped through a bus in the Philippine capital's financial district Tuesday, tearing a huge hole in the vehicle and spraying shrapnel at the passengers. Four people were killed and fourteen wounded.
The force of the explosion, believed to have come from a remotely detonated mortar round, also punched fist-size holes in a concrete wall of a nearby upscale compound in Makati city, officials said.
In a nationally televised statement, President Benigno Aquino III said all government agencies, including the intelligence services, would not stop "until everyone involved in this heinous crime is accounted for."
"We will not allow this situation where there is fear among the people to continue," said Mr. Aquino, who visited the wounded in hospitals late Tuesday and inspected the damaged bus in a police compound.
At least one of the 14 wounded people was in critical condition and a few others have to undergo surgery to remove shrapnel from their feet, Welfare Secretary Dinky Soliman told reporters.
Mr. Aquino and other officials have not named any specific suspects but suggested they included al Qaeda-linked Abu Sayyaf militants, who have been blamed in past attacks on passenger buses, including a 2005 bombing that killed four passengers very near Tuesday's blast.
Mr. Aquino said he directed his national security adviser to reassess threats that reportedly came from terrorist groups last year and that prompted several countries, including Australia, Britain and the U.S., to put in place travel warnings. At the time, the government had not found the threats credible and the warnings infuriated Mr. Aquino.
Investigators were also looking into the background of the wounded and the dead, police Chief Superintendent Jose Arnel delos Santos said, without elaborating. His statement suggested that one of the passengers may have been carrying the explosive when it went off prematurely.
The bus, cruising along a main highway, has just gone past a popular shopping center surrounded by a cluster of hotels and office buildings when it was rocked by the blast, police said. Bus driver Maximo Peligro told reporters he continued driving for another half a block before stopping. Panicked passengers crowded the exit door, prompting him to kick out part of the windshield so people could jump from the vehicle that way.
"The explosion ripped through from behind me and suddenly there was smoke," passenger Annabelle Gozon, who sustained minor wound to her arms, told Philippine television reporters. As passengers began to panic, "I yelled break the door, break the door," she told reporters.
Makati Mayor Junjun Binay, who arrived at the scene minutes after the blast, told reporters he saw flesh and pieces of bone scattered in the bus. Blood spilled down the bus's steps.
"This is an act of terrorism," Mr. Binay said.
Police forces have been put on alert and security in possible targets, including airports, hotels, bus terminals and public places have been strengthened, national police Raul Bacalzo said.
Metro Manila police chief Nicanor Bartolome said an improvised explosive device apparently went off under a passenger seat in the middle of the bus.
Fragments of what appear to be a 60 mm mortar round and cell phone parts were recovered at the scene, two officials, who requested anonymity because of the nature their work, told the Associated Press.
Presidential spokesman Edwin Lacierda said investigators were trying to determine the "signature," or design of the explosive to get a clue on the identity of any group behind the blast.
The government has been fighting decades-long communist and Muslim rebellions in addition to Abu Sayyaf, a small but violent group notorious for bombings, beheadings and kidnappings for ransom. Several passenger buses have also been bombed in the country's volatile south in past years in attacks officials blamed on Muslim rebels and extortion gangs.
Associated Press writers Oliver Teves and Teresa Cerojano contributed to this report.