According to the Seismological Center of the Geophysics Institute of Tehran University, the tremor occurred at 17:59 hours local time (13:29 GMT) and at the depth of 10 km underground.
The epicenter of the quake was located at 48.99 degrees longitude and 35.65 degrees latitude.
No report has so far been released on the likely casualties or losses to property.
Iran sits on major faultlines and is prone to earthquakes on a nearly daily basis.
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