Shallow quake hits Sumatra island
The magnitude 5.9 quake hit in Northern Sumatra, 43 km (27 miles) east of Sibloga, the US Geological Service said.
An official at Indonesia's meteorology agency said the epicentre of the quake, which struck at 1426 GMT, was inland near Tarutung and said there was a potential for damage given its power and its relatively shallow depth.
"We need to find information from there. We haven't received any reports (of damage or casualties)," the official said by telephone.
Indonesia is suffers frequent earthquakes, lying in an area of intense seismic activity where several tectonic plates meet, but it often takes some time to assess damage if the quake hits in remote areas where communications are poor.
Sumatra has been hit by a series of major earthquakes in recent years, including a massive 2004 tsunami whose huge waves caused death and devastation throughout the region, following a quake of more than magnitude 9.