Philippine police in helmets and flak jackets crouched beside a bus with 15 Chinese tourists held hostages inside on Monday after firing shots at the tires in a bid to end a daylong standoff led by a dismissed policeman.

There was no immediate word on casualties. But the Filipino driver who escaped moments before police surrounded the bus in downtown Manila said the hostage-taker, armed with an M16 rifle, had opened fire at the tourists, police officer Roderick Mariano said.