JAKARTA, Indonesia -- A powerful earthquake struck off the coast of eastern Indonesia late Wednesday, prompting villagers to flee to higher ground, but officials said a tsunami was unlikely.

There were no immediate reports of injuries or serious damage.

The U.S. Geological Survey said the magnitude-6.8 quake hit about 161 kilometres (100 miles) northwest of Ternate, the provincial capital of North Maluku, and was centred 41 kilometres (25 miles) below the seabed. The U.S. National Tsunami Warning Center said based on historical records the quake was not sufficient to trigger a tsunami.

George Rajaloa, a resident of Ternate, said by telephone that many people ran out of their homes and away from coastal areas out of fear that there would be a tsunami.

Indonesia is prone to earthquakes due to its location on the Pacific "Ring of Fire," an arc of volcanoes and fault lines in the Pacific Basin. In 2004, a massive earthquake off Sumatra triggered a tsunami that killed 230,000 people in a dozen countries.