According to the Seismological Center of the Geophysics Institute of Tehran University, the tremor occurred at 01:07 hours local time (21:37 Wed GMT) and at the depth of 12 km underground.
The epicenter of the quake was located at latitude of 51.63 and the longitude of 28.14.
No report has so far been released on the likely casualties or damage to property. Force four quake is not strong enough to cause damage.
Iran sits on major fault lines and is prone to near-daily earthquakes.
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