Magnitude 6.3 earthquake strikes Philippines' Mindanao island

The Pacific Tsunami Warning Center says the deep tremor was located 69 km below the seabed.

A 6.3 magnitude earthquake struck off Mindanao island in Philippines on Saturday morning, the United States Geological Survey (USGS) said.

USGS said the quake, which initially reported as of magnitude 6.5, was centered 114km east of Davao on Mindanao. The earthquake occurred at 6.53 am.

Authorities said hotel guests and construction workers were seen running from buildings in Davao due to the tremor, but there were no immediate reports of damage

The Pacific Tsunami Warning Center said the deep tremor was located 69 km below the seabed and it was not expected to cause a tsunami.

An earthquake with a magnitude of 6.3 is often considered to be strong and it is capable of causing severe damage. However, the head of the Philippines' seismic agency, Renato Solidum said the effects of this quake would be mitigated by its location and depth.

"The quake is offshore and relatively deep and shaking is reported to be maximum of Intensity V, hence we expect no significant damage," Solidum told Reuters.

Junrey Quiroa, a security guard on a construction site said around 1,000 workers, who were building the 23-storey Avida Towers nearby evacuated the site.

"That earthquake was strong. We were worried things might fall off so everyone got out of the site," he said.

Dave Cabrera, another security guard at Hotel Uno in downtown Davao, said the earthquake tremor was felt strongly in the city.

"Many guests left their rooms and rushed downstairs. That is the strongest I have felt for this year," Cabrera added.

The Philippines sits on the highly seismically active zone "Pacific Ring of Fire" where many continental plates on the earth's crust keep colliding. Hence, it experiences frequent earthquakes.