Four killed as terrorists blow up bus passengers

Mayor Junjun Binay, of suburban Makati city, said the blast was so powerful that it punched a hole in a nearby concrete fence.

Fragments of what appeared to be a mortar round and cell phone parts were recovered at the scene yesterday.

The bus was approaching a commuter railway station when the blast occurred inside the vehicle, breaking windows and immediately killing a female passenger, said Mr Binay.

Three men were also killed, according to police. It wasn't immediately clear how many people were on the bus, but some were unharmed.

Bus driver Maximo Peligro told reporters he continued driving for several more yards before stopping. Panicked passengers crowded the exit door, prompting him to kick out part of the windscreen so people could jump from the vehicle.

The driver said he smelled gunpowder and the explosion was so loud his hearing was impaired for about 30 minutes.

President Benigno Aquino III said the government had received intelligence last year that terrorist groups were plotting bombings but at the time none of the groups appeared to have the resources to carry out the plans.

He said he directed his national security adviser to reassess those threats, but he declined to name any suspects.

In February 2005, the al-Qaida-linked Abu Sayyaf group set off a bomb on a bus also in Makati, killing four passengers.

Mr Aquino promised that his government 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," he said.

Interior secretary Jesse Robredo pledged to hunt down those responsible.

"It's so senseless and so ruthless that (they) will do this to totally defenceless civilians, ordinary people," he said.