A magnitude 5.9 earthquake hit a town in northwest Turkey early on Wednesday, causing widespread panic but there was no immediate report of major damage, Turkey's Disaster and Emergency Management Presidency said.
The earthquake was centered in the town of Golkaya, in Duzce province, some 200 kilometers (125 miles) east of Istanbul.
It struck at 04:08 am and was felt in Istanbul, in the capital Ankara and other parts of the country. At least 35 aftershocks were recorded.
The quake woke people from their sleep and many rushed out of buildings in panic in the province that has experienced earthquakes in the past.
Power in the region was cut.
Interior Minister Suleyman Soylu said 22 people were being treated in hospitals for injuries sustained during the panic, including from jumping from balconies or windows. One of them was in serious condition, he told private NTV television.
Duzce Gov. Cevdet Atay said schools in the region were being closed as a precaution.
Around 800 people were killed in a powerful earthquake that hit on November 12 1999.
In August of that year, 17,000 people were killed by another powerful temblor which devastated nearby Kocaeli province and other parts of northwest Turkey.
Turkey sits on top of major fault lines and is frequently shaken by earthquakes.