A magnitude 6.2 earthquake struck the Philippines on Thursday, the US Geological Survey said, but there were no immediate reports of damage.
The earthquake struck at a depth of 112 kilometres (77 miles) at around 10:00am (0200 GMT) in waters off Calatagan town, about three hours drive from the capital Manila.
Calatagan police chief Emil Mendoza said he and his staff rushed outside following the tremor, which was also felt over the country's heavily populated heartland, including Manila.
"It was a bit strong. We had to run outside," Mendoza told AFP.
While there were no immediate reports of casualties or damage, disaster authorities had been deployed to assess the earthquake's impact, Mendoza said.
Calatagan disaster officer Ronald Torres said the quake lasted between 30 seconds and a minute.
The state seismological agency warned of aftershocks but ruled out tsunami waves due to the tremor's depth.
The earthquake sent people rushing out of buildings in the capital.
Runways and taxiways at Ninoy Aquino International Airport were temporarily closed to inspect for any damage to the pavement, according to the country's transportation department.
Operation of the capital's metro system was also halted while tracks were checked for possible damage.
Images on social media verified by AFP showed a crane truck at a Manila port as it swayed from the force of the tremor.
Diego Mariano, information officer at the civil defence office, said authorities were still assessing the impact of the quake.
"As of now, no major damage or casualties as of reporting time. Assessment still ongoing," Mariano told reporters in a message.
Quakes are a daily occurrence in the Philippines, which sits along the Pacific "Ring of Fire", an arc of intense seismic as well as volcanic activity that stretches from Japan through Southeast Asia and across the Pacific basin.
In October 2013, a magnitude 7.1 earthquake struck Bohol Island in the central Philippines, triggering landslides and killing more than 200 people.
Old churches in the birthplace of Catholicism in the Philippines were badly damaged. Nearly 400,000 were displaced and tens of thousands of houses were damaged due to the quake.
In 1990, a magnitude 7.8 earthquake in the northern Philippines created a ground rupture that stretched over a hundred kilometres, causing severe damage and killing more than 1,200 people.
