A strong 6.1-magnitude quake struck off northeast Indonesia on Saturday but there were no immediate reports of casualties or damage, the Meteorology and Geophysics Agency here said.
The undersea quake struck at 06:48 IST just 104 kilometres northwest of Ternate town in North Maluku province.
"The earthquake carried no tsunami potential," the agency said in a statement.
Its epicentre was 39 kilometres under the seafloor, the agency said.
The US Geological Survey measured the quake at 5.9.
Indonesia was the nation worst hit by the earthquake-triggered tsunami of December 2004 which 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.