The magnitude 5.6 quake was centered about 50 kilometres southeast of the provincial capital, Banda Aceh, Indonesia's Meteorology and Geophysics office said on its website. "It caused panic among people. Some ran out of houses," said local seismologist Erida Wati, who had initially registered the quake at 5.3 before upgrading it.
United States seismologists also put the quake at 5.6. State news agency Antara reported that scores of people ran to higher ground, fearing an impending tsunami.
Aceh, on the northern tip of Sumatra Island, has seen almost daily earthquakes since the massive one on December 26 that produced a deadly tsunami, killing more than 176,000 people in 11 countries. Earthquakes of magnitude 6 and below are not considered strong enough to trigger a tsunami.