A powerful earthquake with magnitude of 6.2 rocked Nias Island off Sumatra Island early Wednesday, meteorology agency Jakarta said.

The quake epicenter was at 24 kilometers southwest Gunung Sitoli of Nias Island and at 10 kilometers under sea bed, an official of the agency Andri Setiaji said.

He said the quake struck at 00:14 a.m. local time (1714GMT).

"Gunungsitoli town, the closest with the epicenter seems to be the worst hit, with some buildings cracked," he told Xinhua.

The intensity of the quake was 5 MMI (modified mercally intensity) at the town, and 3 to 4 MMI at Sibolga town in Sumatra Island and Singkil town, said Setiaji.

"The report so far we get, there are some buildings crack in Gunung Sitoli," he said.

The official said resident in harsh fled their home as the quake took place.

"People waked up and panic, they fled homes. They are scared and still stay outside," he said after receiving report from the Island.

Over 170,000 people were killed in December 2004 after a tsunami hit Aceh province in northern tip of Sumatra Island along with other south and southeastern Asian countries.

Indonesia sits on a vulnerable quake hit zone called the " Pacific ring of Fire", where two continental plates meet that cause frequent seismic and volcanic movements.

(Xinhua News Agency January 23, 2008)