Iranian news agencies made no immediate mention of casualties or damage, but reports were preliminary.
The quake hit at 4:43 pm (1223 GMT) with an epicentre about 60 kilometres (40 miles) northeast of Tabriz, at a depth of 10 kilometres (six miles), according to the Seismological Centre.
The US Geological Survey, which monitors earthquakes worldwide, confirmed the temblor near the city which has a population of 1.5 million people.
It measured 6.2 on the Moment Magnitude Scale used for quakes stronger than 5.
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