"A strong earthquake occurred at (9:10 a.m. EST, 1410 GMT) on Saturday, November 19," the USGS said on its Web site. "The magnitude 6.5 event has been located in Simeulue, Indonesia," an island off Sumatra about 900 miles (1,440 km) northwest of Jakarta. An official at Jakarta's Meteorology and Geophysics Agency said the quake measured 6.2 magnitude and was centered in the ocean near Simeulue. Asked if it could generate a tsunami, he said: "I don't think so. It's already been more than one hour and there have been no reports of a tsunami."
He said, however, the quake was felt by residents on mainland Sumatra island to the west. USGS geophysicist John Bellini said no damage or injuries were reported.
On Dec. 26 of last year a 9.15 magnitude quake off the Indonesian coast triggered a tsunami that killed as many as 232,000 people in the Indian Ocean region. The region has been hit by many aftershocks and tremors since the quake.
Earlier this week Indonesia installed two buoys and a pressure sensor on the ocean bottom off of Sumatra as part of a tsunami early warning system to prevent a repeat of last year's tragedy.