Prime Minister Recep Tayyip Erdogan said at least 93 people were killed in the city of Van and 45 others died in Ercis, an eastern city close to the Iranian border.
The Turkish Red Crescent said dozens of buildings collapsed in Ercis and 10 buildings collapsed in Van.
Officials said hundreds of people were injured and some people remained trapped under rubble. Rescue efforts were continuing through the night.
The quake struck at 1:41 p.m. and was centered in the village of Tabanli in Van province, said Turkey’s Kandilli Observatory and Earthquake Research Institute.
U.S. scientists recorded more than 100 aftershocks in eastern Turkey within 10 hours of the quake, including one with a magnitude of 6.
The earthquake also shook buildings in neighboring Armenia and Iran.
-- Times staff and wire reports
Photo: Residents sit along streets after a powerful earthquake struck eastern Turkey. Credit: European Pressphoto Agency