Almost 60 aftershocks recorded as of 7 p.m.

MANILA, Philippines (4th UPDATE) - A strong earthquake struck off the Philippine west coast that shook the capital city of Manila and its outskirts on Thursday afternoon, the Philippine Institute of Volcanology and Seismology (Phivolcs) said.

In a bulletin issued by Phivolcs, the quake measuring magnitude 6.0 on the Richter scale, struck at 27 kilometers southwest of Lubang Island in Mindoro province at 1:29 p.m.

Phivolcs said the quake's depth was shallow at 25 kilometers and was tectonic in origin.

The quake was felt the strongest at Intensity 5 in the following:

- Looc, Lubang Island
- Manila

Intensity 4 was felt in:
- Quezon City
- Mandaluyong City
- Makati City
- Pasay City
- Taguig City
- Pasig City
- Talisay town in Batangas province,

It was Intensity 3 in:
- Bagac town in Batangas province
- Canlubang in Laguna
- Clark in Pampanga
- Rosario and Trece Martires in Cavite province
- Marikina City
- Tagaytay City

It was Intensity 2 in
- Calamba town in Laguna province
- Legaspi City in Albay
- Puerto Galera in Oriental Mindoro

Phivolcs Director Renato Solidum said they were not expecting any damages from the earthquake, and there was no need to issue a tsunami warning.

"This is not significant in terms of magnitude," Solidum said, adding that only minor aftershocks may also take place.

The 10-level Phivolcs Earthquake Intensity Scale or PEIS describes Intensity 5 as: Strong - Generally felt by most people indoors and outdoors. Many sleeping people are awakened. Some are frightened, some run outdoors. Strong shaking and rocking felt throughout building. Hanging objects swing violently. Dining utensils clatter and clink; some are broken. Small, light and unstable objects may fall or overturn. Liquids spill from filled open containers. Standing vehicles rock noticeably. Shaking of leaves and twigs of trees are noticeable.

Intensity 2, meanwhile, is described as: Slightly Felt - Felt by few individuals at rest indoors. Hanging objects swing slightly. Still water in containers oscillates noticeably.

Two quakes?

In a separate report, the United States Geological Survey (USGS) placed the earthquake's magnitude at 6.1.

The USGS said there were actually 2 quakes just seconds apart, with the first at magnitude 6.0 and barely under the surface, while the 2nd was 33 kilometers deep.

The National Disaster Coordinating Council said it had no immediate information on damages or injuries after the quake.

"So far, I haven't received any reports of damage or casualty. Nothing on SMS, nothing on my telephone," Glenn Rabonza, head of the Office of Civil Defense (OCD), told Reuters.

Residents in the Makati central business district said they felt the tremor and that office buildings swayed. Traffic in the Makati business district was flowing as usual and pedestrian numbers were normal.

The USGS said the quakes were centered around 100 km (66 miles) west of the city of Batangas, south of Manila.

Based on reports from Lubang Island in Mindoro, Rabonza said residents there felt a "strong" quake but there were no reports of damages, as of posting.

However, he said local authorities are checking whether there were damages to bridges and other structures such as the cathedral.

"We have no reports yet, so everybody is trying to determine (whether there are damages)," Rabonza said.

In Batangas, he said the provincial disaster council reported no damages as well.

In Metro Manila, Rabonza said he was in Pasay when the quake happened and that people felt it there.

However, he said that if there were damages in Metro Manila, he said the OCD would already have gotten reports since the reporting system in the national capital is fast.

Over an hour since the quake happened, Rabonza said he has not received reports of damages.

58 aftershocks as of 7 p.m.

Solidum, in a phone interview Thursday evening, said that 58 aftershocks have been recorded as of 7 p.m.

The Phivolcs chief said, however, that no reports of damages are expected since the aftershocks, which occurred in the vicinity of the quake’s epicenter, were weak and were hardly felt in other parts of the country.

Solidum also said that it could not be predicted if aftershocks would continue to occur saying that these are unpredictable. - with reports from Reuters and Agence France-Presse