Reports from the area said the relatively shallow quake just after 6 a.m. (7 p.m. EDT) hit 55 km (33 miles) southeast of Kendari, the regional capital of over 300,000 people in Southeast Sulawesi.

At least three strong aftershocks followed the initial magnitude 6.2 quake over the next couple of hours, officials said.

"There are houses damaged. People are panicking and have rushed out from their houses," said Asep Jaelani, an official at South Sulawesi's quake agency. "No tsunami warning has been issued as the epicenter of the quake was inland."

He had no reports of casualties.

"It will be felt strongly there but it won't be devastating," Rahmat Triyono, an official at Indonesia's national meteorology agency, said.

"Looking at the map, the epicentre is inland, but just at the tip, and there are several small islands there, so it will be felt there, too."

The United States Geological Survey said the quake occurred at 2307 GMT, 67 miles east of Baubau at a relatively shallow depth of 5.8 miles.