Rescuers searched for survivors amid the rubble of collapsed buildings in eastern Turkey on Sunday after a powerful 7.2 magnitude earthquake struck, killing at least 138 people.

The earthquake struck at 1:41 p.m. local time

Prime Minister Tayyip Erdogan reported at least 93 people died in the city of Van and 45 died in the city of Ercis about 60 miles north near the country’s border with Iran.

Earlier, Kandilli Observatory general manager Mustafa Erdik estimated 1,000 buildings are damaged and hundreds have died.“It could be 500 or 1,000,” he said.

President Barack Obama said “we have been following reports … with great concern.” He said the U.S. was “ready to assist the Turkish authorities.”

“This earthquake is a reminder of the many deadly seismic events that Turkey has suffered in the recent past,” the U.S. Geological Survey said on its website on Sunday.

The 7.6 magnitude Izmit quake in 1999 killed 17,000 people, the USGS noted. A 1976, 7.3 magnitude quake near the border with Iran quake killed several thousand. A 7.8 magnitude quake in 1939in Erzincan.