The quake struck at a depth of 6 kilometers (3.7 miles) at 7:44 a.m. local time (0444 GMT) off Greece's Rhodes island and 57-kilometer off Turkey's southwestern Muğla province.
The quake was felt in some districts of Muğla and in neighboring provinces.
Muğla Governor Esengül Civelek said no damage or injuries were reported.
Last week, Turkey's most populous city Istanbul was shook by a 5.8-magnititude earthquake, causing eight injuries and momentary panic across the city.
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