An earthquake with a magnitude of 6.1 hit offshore the Indonesian island of Sumatra, the Indonesian Meteorology and Geophysics Agency said on Thursday.

The United States Geological Survey put the quake, which occurred at 1116 GMT, at a magnitude of 6.0.

Senior Indonesian seismologist Fauzi told Jakarta-based Radio Elshinta the earthquake appeared too small to trigger a tsunami.

"We don't need to be concerned about the possibility of a tsunami. The scale was too low for a tsunami. It could be felt though, so we hope there won't be any damage," Fauzi said.

A seismologist at the agency's branch in North Sumatra province said that no damage had been reported from the closest areas to the epicenter.

"It happened near Nias island but we have not received reports of any damage from there. It has been an hour so I think there has been no indication of a coming tsunami," said Buha Simanjuntak.

A government official on Nias also said there was no indication of damage or casualties, but people fled homes and buildings after feeling the tremor.

The Pacific Tsunami Warning Center in Honolulu, Hawaii, gave no immediate warning of a tsunami. The quake's magnitude was under its threshold of 6.5 for a specific tsunami warning.

In March 2005, a powerful earthquake devastated Nias island, off the west coast of northern Sumatra, killing hundreds of people and leaving tens of thousands homeless.

Earthquakes are frequent in Indonesia, the world's fourth most populous country. Its 17,000 islands sprawl along a belt of intense volcanic and seismic activity, part of what is called the "Pacific Ring of Fire."

Note

magnitude: n. 量级
Sumatra: n. 苏门答腊岛(在印尼西部)
tsunami: n. 海啸
seismologist: n. 地震学家
epicenter: n. 震中, 中心
tremor: n. 震动, 颤动
sprawl: v. 四肢伸开地坐(或卧), 爬行, 蔓生, 蔓延