A tsunami alert was issued for a brief period after the powerful jolt, but was canceled once instruments failed to detect any significant change in sea level.
Roads had quickly become jammed with vehicles carrying thousands of people to higher ground before the alert was lifted.
"I'm scared and traumatized. The best thing for us to do was to run to higher ground as a precaution," said Aminah, a resident of the seaside village of Alue Naga who carried her child on her back. She made the comments to the Jakarta Post.
Some residents near the city of Banda Aceh said the shaking seemed to be as strong as the one that triggered the devastating Indian Ocean Tsunami of December 2004, but it just didn’t last as long.
Sunday's temblor was reportedly felt widely across northwestern parts of Sumatra just seconds before 1 p.m. local time.
The epicenter was beneath the Indian Ocean just off Sumatra about 120 miles southwest of Banda Aceh. It occurred at a depth of 28 miles, according to the U.S. Geological Survey.
The Sumatra region has been hit by a series of devastating earthquakes since the 9.1 magnitude temblor and subsequent tsunami of 2004.