A local tsunami alert was issued after an earthquake of magnitude 7.4 struck 140 miles (225 kms) south of Banda Aceh in Sumatra, Indonesia, the country's quake agency and the United States Geological Survey (USGS) reported on Sunday.
"A destructive widespread tsunami threat does not exist based on historical earthquake and tsunami data," the USGS said. "However there is the possibility of a local tsunami that could affect coasts located usually no more than a hundred kilometers from the earthquake epicenter."
Indonesian authorities said they were still trying to get details of the quake, which happened at 0559 GMT. "It could be felt quite strongly but we don't know if there were casualties or buildings damaged," said Subagyo, from the Indonesian bureau of meteorology's quake monitoring centre.
The Indonesian archipelago stretches across a seismically active area known as the Pacific Ring of Fire and is prone to earthquakes and volcanoes.
A 2004 Indian Ocean tsunami on Sumatra island killed 170,000 people in Aceh province alone, while more than 1,000 people died after a powerful quake hit the city of Padang last September.