An earthquake measuring 5.9 on the Richter scale struck Iran's southern province of Bushehr on Sunday, state television reported.
The epicentre of the quake was the town of Rig and hospitals in nearby cities and provinces were on alert, with rescue teams and 50 ambulances sent to the area, a regional official told state TV.
Electricity and landline telephone and internet in the regional city of Gonaveh had been cut off "and people are taking to the streets for fear of earthquakes," news agency Tasnim reported.
An Iranian government official told Reuters there were no reports of damage at the Bushehr nuclear complex, situated on Iran's Gulf coast.
The quake was centred 100 km away from the plant and was relatively shallow - only 10 km deep according to Iranian media - which would have amplified the shaking.
Media reported nine aftershocks and posted pictures that showed collapsed mud brick walls in some villages.
Two people were injured in Gonaveh and were being taken to hospital, state media quoted the head of the Bushehr University of Medical Sciences, Saeed Kashmiri, as saying.
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