The Seismological center of Khuzestan province affiliated to the Geophysics Institute of Tehran University registered the quake at 02:19 hours local time (2249 GMT Friday night).
The epicenter of the quake was located in an area 49.1 degrees in longitude and 30.5 degrees in latitude.
Iran sits astride several major faults in the earth's crust, and is prone to frequent earthquakes, many of which have been devastating.
The worst in recent times hit Bam in southeastern Kerman province in December 2003, killing 31,000 people - about a quarter of its population - and destroying the city's ancient mud-built citadel.
The deadliest quake in the country was in June 1990 and measured 7.7 on the Richter scale. About 37,000 people were killed and more than 100,000 injured in the northwestern provinces of Gilan and Zanjan. It devastated 27 towns and about 1,870 villages.
Around three months ago, two quakes in Northwestern Iran also claimed the lives of 306 people and injured more than 4500 others.
An earthquake measuring 6.2 on the Richter scale jolted Ahar in East Azerbaijan province at 16:00 hours local time (1130GMT) on August 11. Almost an hour later another quake with magnitude 6 on the Richter scale jolted Varzaqan at 17:04 hours local time (1234GMT) in the same province.
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An earthquake measuring 3.6 on the Richter scale hit the town of Bandar Mahshahr in Khuzestan province, Southwestern Iran, on Saturday.
News ID 183456
