At least three people including two children were killed and dozens injured by an earthquake that jolted northern Iran, state radio reported on Saturday.

The quake, which the seismological centre said had a magnitude of 5.9, struck Semnan province on Friday night and was followed by 15 aftershocks. The US Geological Survey said it measured 5.7.

'Two children and a woman were killed in the quake and 40 others were injured,' state radio quoted Morteza Aliabadi, a senior local official, as saying. 'Over 15 villages in the province were also damaged.'

Authorities said the quake had had no effect on fault lines beneath the capital Tehran, where the quake was also felt.

The US Geological Survey said the quake's epicentre was about 150 km south of the city of Gorgan, northeast of Tehran, at a depth of 10 km.

Iran, the world's fourth-largest oil producer, is criss-crossed by fault lines and often experiences earthquakes. In 2003, an earthquake flattened the desert city of Bam and killed 31,000 people.-Reuters