A strong 6.2-magnitude quake struck in Indonesia's north Sulawesi province on Sunday but there were no reports of damage or injuries, the geophysics agency said. The quake hit at 1.23pm about 20 kilometres (12 miles) north-east of Melonguane city at a depth of 50 kilometres.

No tsunami alert was issued.

'Tremors are felt in the area but not significant ones. There's no report of damage,' agency official Suharjono told AFP.

The Indonesian archipelago sits on the Pacific Ring of Fire where continental plates meet, causing frequent seismic and volcanic activity.