MANILA, Philippines — Philippine police in helmets and flak jackets crouched beside a bus with 15 Chinese tourists held hostages inside today 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.

Police used hammers to smash side windows, door and windscreen, but still did not enter the vehicle and there was no movement seen inside.

The gunman earlier released nine hostages — leaving 15 inside — and demanded his job back to free the rest.

Hours after seizing the bus, he released two women, three children, a diabetic man and three Filipinos — including a tour guide and a photographer, police said.

The hostage-taker, identified as former Senior Inspector Rolando Mendoza, 55, was demanding he be given back his job on the police force a year after he was fired, Manila Police Chief Rodolfo Magtibay said.