A strong earthquake measuring 6.9 on the Richter scale rocked eastern Indonesia's Sulawesi region on Saturday morning, sparking panic in seaside communities as residents fearing a tsunami fled their homes for higher ground.

The Indonesian Meteorological and Geophysical Agency in Jakarta said the quake was large enough to cause casualties, damage and a tsunami, although there were no immediate reports of any deaths or big waves.

"A tsunami is a possible situation," said agency official Rachmat Triono, adding that the epicenter was about 40 miles southwest of the island of Buton and 20 miles under the Flores sea.

"The jolt was felt in Buton island and waters around it rose three to four meters but we don't know whether it has swept into the island," he told Reuters.

The quake struck at around 8.00 a.m. (7 p.m. EST).

In one part of Buton island, women and children wept as they fled to an old palace on a nearby hill, leading news channel Radio El Shinta said. It was unclear how many people live on the island.

The U.S. Geological Survey Web site said the earthquake was measured initially at a magnitude of 6.5.

The tremor follows a massive earthquake of magnitude 9.0 off Indonesia's Sumatra island on Dec. 26 that triggered huge tsunami waves that left widespread devastation and are feared to have killed as many as 300,000 people around the Indian Ocean.

That quake has spawned hundreds of aftershocks and bred fear of tsunamis across Indonesia, one of the most earthquake-prone countries in the world.

PHOTO CAPTION

Acehnese volunteers carry a recovered body of the Dec.26, tsunami victim, out of the jungle Thursday Feb. 17, 2005 in Banda Aceh. (AP)