MANILA, Philippines (AFP) — A 6.8-magnitude earthquake struck off the coast of the southern Philippines on Saturday, the United States Geological Survey said, but no tsunami warning was issued and there were no immediate reports of damage.

The shallow quake hit just before 6:30 am (2230 GMT) about 20 kilometres (12 miles) from the village of Barcelona on the east of Mindanao island, the USGS said.

It did not trigger a tsunami alert, according to the US Tsunami Warning System and the Philippine seismological agency.

The local seismological agency also said no damage was expected from the earthquake, but it warned of aftershocks.

In Lingig municipality, where Barcelona is located, local disaster officer Ian Onsing said he was woken by the shaking.

“The shaking was quite strong. The things around here were moving. I guess, the shaking took around 10-15 seconds,” Onsing told AFP by telephone.

“I’m not expecting any more damages, but we will go around the area again around 8:00 am just to be sure,” he said.

“So far, there are no reported casualties or damages. We are now monitoring the shores for any rough movement.”

Earthquakes regularly strike the Philippines, which sits along the Pacific Ring of Fire, an arc of intense seismic and volcanic activity that stretches from Japan through Southeast Asia and across the Pacific basin.

Most are too weak to be felt by humans but strong and destructive quakes come at random with no technology available to predict when and where they will happen.

In December, a 7.6-magnitude quake struck off Mindanao, briefly triggering a tsunami warning.

That sent residents along the east coast of the island fleeing buildings, evacuating a hospital and seeking higher ground.

At least three people died.