JAKARTA - A strong 6.6-magnitude earthquake struck off the eastern Indonesian province of Maluku early Thursday, prompting a tsunami alert that was later lifted, the meteorology and geophysics office said here.

The earthquake, which struck at 2:58 am (2000 GMT Wednesday), was centred 275 kilometres (171 miles) southwest of Maluku province, some 10 kilometres under the seabed, a text message from the office said.

"There is the potential for a tsunami," it added.

A second message sent one hour later said that the alert had been lifted.

The United States Geological Survey measured the quake at 5.9 and said it occurred 299 kilometres west of Saumlaki, in Indonesia's Tanimbar Islands, and 341 kilometres east of the East Timorese capital Dili.

A policeman stationed in Saumlaki district who identified himself as Kamanasa told AFP that the quake was not felt in the surrounding area.

"We didn't feel any shakes here," he said.

Yanuarsih, from the meteorological agency in Jakarta, told AFP that the agency had not received any reports of damage from the quake.

Tsunami warnings are routinely issued in Indonesia for strong quakes occurring at a depth of 10 kilometres or less.

Equipment is not currently in place to measure a change in water depth commensurate with a tsunami forming off a coast.

Dili is currently under an evening-to-dusk curfew following failed assassination bids on its president and prime minister on Monday.

Indonesia sits on the Pacific "Ring of Fire" where continental plates meet, causing frequent seismic and volcanic activity.

The archipelago nation was hardest hit by the earthquake-triggered Asian tsunami in December 2004. Some 168,000 people alone were killed in Aceh province on the northern tip of Sumatra.