Feb. 26 (Bloomberg) -- Dozens of homes were damaged and a health clinic was leveled when an earthquake measuring 6.6 hit near the Indonesian island of Sumatra today, officials said.

The quake, which struck the Mentawai islands region at 4:02 a.m. local time, was the third to hit the area in about 12 hours, the U.S. Geological Survey said on its Web site.

``Fortunately the worst-hit area has a small population,'' Rustam S. Pakaya, head of crisis management at Indonesia's Health Ministry, said by telephone. ``Workers are combing the area and so far there haven't been any reports of casualties.''

The earthquake struck 150 kilometers (95 miles) south- southwest of Padang on Sumatra at a depth of 39 kilometers, according to the USGS. The U.S. Pacific Tsunami Warning Center and the Japan Meteorological Agency said in e-mailed alerts there was a ``very small possibility'' of a ``destructive local tsunami'' in the Indian Ocean.

Residents whose homes were damaged in Sikakap on the Mentawai islands were offered temporary shelter, Pakaya said, adding communication with the area was disrupted.

The USGS earlier said the quake was magnitude 6.9. A magnitude 7 earthquake struck at 3:36 p.m. local time yesterday and a temblor measuring 6.3 hit at 1:06 a.m. today. There were no immediate reports of damage or casualties from those quakes, Indonesia's Meteorology and Geophysics Office said.

There have been hundreds of earthquakes in Indonesia since a 9.1 temblor in 2004 caused a tsunami that swept across the Indian Ocean, devastating coastal communities and leaving more than 220,000 people dead or missing in Indonesia, Sri Lanka, India, Thailand and other countries. The Indonesian archipelago lies in a region where tectonic plates are constantly shifting.

Yesterday's quake hit an area 165 kilometers southwest of Muko-muko, in Bengkulu province, at a depth of 10 kilometers, the Indonesian agency said.

The temblor sparked panic in Bengkulu and the west of Sumatra, sending people into the streets, Jakarta-based ElShinta radio reported. Tremors also rocked buildings in downtown Singapore, located 587 kilometers from the epicenter.

To contact the reporter on this story: Karima Anjani in Jakarta at kanjani@bloomberg.net

Last Updated: February 25, 2008 23:51 EST