Quake jolts sparsely populated area in Iran
It said the epicentre of today's quake was in the Shonbeh district, some 120 kilometres southeast of Bushehr, a Persian Gulf town that is home to Iran's first nuclear power plant, built with Russian help.
Last year a magnitude-6.1 quake killed at least 37 people and injured hundreds more in the same area. It did no damage to the plant, which is built to resist earthquakes up to magnitude 8.0.
Iran experiences frequent earthquakes.
In 2003, some 26,000 people were killed by a magnitude-6.6 quake that flattened the historic southeastern city of Bam.