Two bomb blasts went off in southern Philippine city Zamboanga, wounding 24 people and knocking off power.
A homemade bomb went off underneath a parked van along a street in Zamboanga city where commuters were waiting for a ride home, wounding at least five people, damaging the van and a motorcycle, the officials said.
The blast at 7:15 p.m. (1115 GMT) scattered the van's metal parts several meters (yards) away and partly damaged a nearby wooden house, said Superintendent Jose Bayani Gucela, Zamboanga's deputy police chief.
While police investigators were sifting through the wreckage of the van, a second bomb struck an inn atop a restaurant, Zamboanga Mayor Celso Lobregat said by telephone. A third bomb was found nearby and defused, he added.
The blast knocked off power in the neighborhood and shattered the restaurant's glass panels, police and radio news reports said. A hospital official said at least 19 people were wounded.
Police cordoned off the two blast sites and business establishments immediately closed down. Firetrucks, ambulances and police cars stood by.
No group claimed responsibility for the bombings and investigators were trying to determine the identity and motive of the attackers, Gucela said. Police set up road checkpoints to thwart other possible bomb attacks.
Zamboanga, which lies 860 kilometers (530 miles) south of Manila, is a bustling seaport that has been hit by deadly bombings in the past and continues to receive threats from Muslim militants, including the al-Qaida-linked Abu Sayyaf Muslim extremist group, the AP reports.
The city of more than 600,000 people hosts the headquarters of the military's Southern Command, the staging ground for offensives against Muslim and communist guerrillas in the sprawling Mindanao region.
Several U.S. military soldiers were in the military camp, continuing a years-long anti-terrorism training of Filipino troops.