An earthquake measuring 4.7 on the Richter scale shook northwestern Turkey on Monday evening with its epicenter in the town of Bilecik, CNN Turk reported.
The quake occurred at a depth of 5 km at 19:09 local time (1600 GMT) in Bilecik, which is around 274 km southeast of Istanbul, the Kandilli Observatory stated.
The quake was also felt in the cities of Istanbul, Kocaeli, Bursa, Sakarya and Eskisehir.
No reports of physical or material damage were immediately available.
Turkey is fundamentally vulnerable to earthquakes because of its geographical location.
The country sits between two huge tectonic plates, Eurasia and Africa/Arabia, which are inexorably grinding into one another, north to south.
Earthquake safety was forced firmly on to Turkey's political agenda following the Izmit tremors in 1999, which killed more than 17,000 people.