JAKARTA - A 5.7-MAGNITUDE quake struck off the Indonesian island of Sulawesi on Tuesday but there was no threat of a tsunami and no immediate reports of damage, the Meteorology and Geophysics Agency said.

The undersea quake struck at 10.20 am 157 kilometres northeast of Melonguane town in North Sulawesi province.

'There were no reports that the quake was felt anywhere,' agency geologist Subagio said.

There was no danger of a tsunami being triggered by the quake, whose epicentre was 107 kilometres under the seabed, he added.

Indonesia was the nation worst hit by the earthquake-triggered tsunami of December 2004 that killed some 168,000 people in Aceh province alone.

The archipelago nation sits on the Pacific 'Ring of Fire' where continental plates collide, causing frequent seismic and volcanic activity. -- AFP