A strong 6.4-magnitude earthquake struck Indonesia's remote eastern Sumba island Monday but there were no immediate reports of damage or injuries, seismologists said.

The quake struck at 7:52 pm (1052 GMT) with an epicentre 107 kilometres (67 miles) northwest of the main island town of Waingapu, the Indonesian Meteorology and Geophysics Agency said.

It was measured at a depth of 86 kilometres.

Widyanto, an official from the agency, said from Waingapu there appeared to be no damage or injuries in areas near the epicentre.

"People panicked and ran out of their homes. But so far, we have not received reports of casualties or damage to buildings," he said.

The United States Geological Survey measured the quake at a magnitude of 6.1.

Indonesia was the nation worst hit by the earthquake-triggered Indian Ocean tsunami in December 2004 that killed more than 220,000 people, including over 168,000 people in Indonesia's Aceh province and Nias island.

Indonesia sits on the Pacific "Ring of Fire", where the meeting of continental plates causes high volcanic and seismic activity.

Nearly 700 homes as well as office buildings, schools and health clinics were damaged when a 7.2-magnitude quake struck the remote Talaud Islands in North Sulawesi province in February.