A powerful 6.3-magnitude quake shook Indonesia's central Sulawesi province on Saturday, damaging buildings and injuring at least three people.

Panicked residents in two mountainous districts near the epicentre ran from their homes into the streets as the quake rocked their villages for around 15 seconds.

An AFP reporter in the provincial capital Palu also felt violent shaking.

"There are three villages near the epicentre where 23 homes have been damaged to some extent, and those villages are experiencing a blackout," head of Sigi district Disaster Mitigation Agency Rezmin Laze told AFP.

"At least three people have been injured by falling debris and rescuers are having difficulty evacuating them to Palu."

The quake hit around 56 kilometres (35 miles) southeast of Palu, according to the US Geological Service (USGS), at around 5:40 pm (0940 GMT) at a depth of 20 kilometres (12 miles).

Parigi Moutong and Sigi districts were the hardest-hit, according to Indonesia's Meteorology, Climatology and Geophysics Agency.

Herlina, a receptionist at the Tunas Harapan Hotel in the town of Parigi, told AFP the shaking sent guests running into the street.

"Everyone was scared... but everything's fine now. There was no damage to the hotel and I haven't seen any damage on the street," said Herlina, who like many Indonesians goes by one name.

USGS initially reported the quake's magnitude at 6.6, while Indonesia's geophysics agency measured it at 6.2.

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