The fatalities occurred near the epicenter on Qeshm Island, just off Bandar Abbas, in the strategic oil route of the Strait of Hormuz.
Iran’s state television said the tremor lasted about 30 seconds at 2:30 p.m. local time, and was followed by at least 10 aftershocks, the most powerful registering a magnitude of 4.8.
Initial seismic signals from the powerful quake prompted brief speculations in world capitals that Iran had conducted a nuclear test.
Across the Persian Gulf from the epicenter, residents in Dubai and neighboring Arab Emirates reported feeling a quake that lasted less than a minute. The shaking sent office workers rushing out of some of the high-rise towers in Dubai.