A powerful 7.9-magnitude quake struck off Indonesia's Sumatra island on Wednesday but no tsunami warning was issued, geologists said.
The quake struck at sea at 5:16 pm (1016 GMT) at a fairly deep 87 kilometres (54 miles), 53 kilometres northwest of Padang city in West Sumatra province, the United States Geological Survey said in an alert.
Local news channel Metro TV reported buildings had collapsed and fires had started in Padang, a city of 900,000, where panicked residents had run onto the streets as the quake hit.
Indonesia's geophysics and meteorology agency did not issue a tsunami alert.
Indonesia sits on the Pacific "Ring of Fire," where the meeting of continental plates causes high volcanic and seismic activity.
A quake on the main island of Java earlier this month killed 123 people.