The quake's epicenter was 51 km (31 miles) northeast of Sumbawa Island and 10 km (6.2 miles) beneath the seabed, according to the agency's official report. Two aftershocks measuring 5.1 and 5.2 followed, but there were no tsunami warnings issued or casualties reported.
According to the chief of BMG's Sumbawa department, Setiawan, the Moyo Island, closest to the quake's epicenter, was the hardest hit with dozens of buildings destroyed.
"Damage at Sumbawa is insignificant, mainly cracks in houses," he said.
Other media reported that over 120 houses were destroyed and some 117 suffered minor damage.
The Indonesian archipelago is located at the Pacific Ring of Fire, an area of frequent earthquakes and volcanic eruptions encircling the basin of the Pacific Ocean. Indonesia was worst hit by the December 26, 2004 earthquake and tsunami, which killed more than 225,000 people in 11 countries.
