The U.S. Geological Service said the quake's magitude was 6.1 and it struck at 1100 GMT about 53 km (33 miles) west-southwest of Bandar Abbas, which is home to an oil refinery and the country's main navy base.
"All our rescue groups are on alert in Bandar Abbas and (nearby) Qeshm island. We have sent groups to the area. There is the possibility of casualties and fatalities," Hazbavi earlier told Reuters.
Iranian reports variously described the quake as 6.0 and 7.5 on the Richter scale.
The earthquake in southern Iran was 7.5 on richter scale, Iran's Fars News Agency said, citing Iranian official.
State television said the tremor lasted about 30 seconds but was followed by at least 10 aftershocks, the most powerful measuring 4.8 on the Richter Scale.
Iran's state-owned Press TV described the tremor as strong but said there were no reports of casualties.
"Its centre was Bandar-e Khamir. It might have damaged old parts of the place but we still don't have any (casualty) reports," an Interior Ministry official told Reuters.
OIL FACILITIES UNDAMAGED
The earthquake did not damage oil facilities in the port city of
"Fortunately, there was no damage to the oil industry's facilities at Bandar Abbas," Hojjatollah Ghanimifard, vice president for investment affairs at the National Iranian Oil Company, told Reuters.
The quake hit at 1100 GMT about 53 km (33 miles) west-southwest of Bandar Abbas at a depth of 34.6 miles (55 km), the U.S. agency said.
Residents in the United Arab Emirates, across the Gulf from Iran, reported feeling a slight tremor.
Iran sits astride several major faults in the earths 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 the city’s population -- and destroying the city’s ancient mud-built citadel.
Tehran alone sits on two major fault lines, and the 7.5 million residents of the capital fear a major quake.