A strong earthquake jolted a major port city on the Gulf coast of southern Iran on Wednesday, the official IRNA news agency reported, the second to strike in a week.

The five-magnitude quake hit at 10:13 pm (1843 GMT) west of the port of Bandar Abbas near Bandar Khamir, IRNA said, adding that frightened Bandar Abbas residents had rushed out into the streets.

"No damage has been reported yet and experts are following the matter," said Yaser Hezbavi, a local natural disasters management official.

IRNA said a second quake jolted Qeshm island off the coast from Bandar Abbas -- which is home to an oil refinery and the country's main naval base -- without specifying its magnitude.

"The electricity is cut off in Qeshm and people are in the streets," it said.

Last Wednesday a 6.1 magnitude quake hit Qeshm, a popular tourist and free trade island which lies in the strategic Strait of Hormuz, killing seven people and injuring 47.

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 the southern city of Bam in December 2003, killing 31,000 people -- about a quarter of its population -- and destroying the city's ancient mud-built citadel.