It said said the quake hit the remote mountainous Kahnuj region in Kerman province, damaging houses in three villages but causing no deaths.
"Fortunately, there is no indication so far ... about any loss of life in this earthquake," a senior official from the Interior Ministry's office dealing with emergencies told the radio.
"The level of damage has been at a minimum, something for which we should thank God," the official said.
The quake was also felt in adjoining Fars and Hormozgan provinces, damaging homes in two villages in the Hajiabad area near the Gulf port of Bandar Abbas, he added.
A slight tremor was felt in Dubai in the United Arab Emirates, on the other side of the Gulf.
A strong earthquake hit the region two years ago, killing five people.
Iran is often hit by earthquakes. Its worst quake, measuring 7.3 on the Richter scale, killed 35,000 people in 1990.
- Reuters - Thomson Reuters Foundation
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