Panama City - A strong earthquake of 6.2 magnitude and at a depth of 48 km struck Panama near the Costa Rica border overnight, the U.S. Geological Survey said on Wednesday.

The quake hit 56 km west southwest of David, Panama, at 1:11 a.m. local time (0611 GMT).

The tremor was felt in Costa Rica's capital of San Jose, but that country's emergency commission said there were no reports of damages there.

A local radio station in Panama received calls from people in the area who said they felt the quake strongly and also felt several aftershocks.

Initial checks by emergency workers near the quake's epicentre found no immediate signs of serious damage or landslides, a man identifying himself as a Red Cross worker told Panamanian radio.

The USGS also said there were no immediate reports of damage or injuries.

The USGS originally said the quake reached a magnitude of 6.5 at a depth of 16 km.