A powerful earthquake struck eastern Turkey late on Friday, killing at least 18 people and collapsing buildings in towns near the centre of the tremor, which was strong enough to be felt in several neighbouring countries.

The magnitude 6.8 quake shook Elazig province, about 550 km (340 miles) east of the capital Ankara, and was followed by dozens of aftershocks.

Sixteen people were killed in Elazig and four more in the neighbouring province of Malatya, Turkey's Disaster and Emergency Management Authority (AFAD) said early on Saturday. Some 920 injured were in hospitals in the region, it said.

Interior Minister Suleyman Soylu said emergency workers were searching for 30 people under the rubble.

State broadcaster TRT showed footage of dozens of workers in the dawn light using shovels to dig out a partly collapsed building in Elazig. Windows were smashed and balconies from at least four storeys had crashed to the ground.

Rescue teams have been deployed to affected areas to help people, according to Turkey's Disaster and Emergency Management Authority.

Western Turkey was rocked by a series of tremors, including one that measured magnitude 5.4 on Thursday, when four people were injured and 15 buildings suffered slight damage.