A strong earthquake rattled the Indonesian island of Java on Friday, sending panicked people into the streets of the capital city, Jakarta.

The U.S. Geological Survey put the quake's magnitude at 6.3 -- lowering it from 6.5.

The epicenter was located in the Sunda Strait -- the narrow body of water between Java and Sumatra islands, about 115 miles (185 km) southwest of Jakarta, according to the USGS.

It struck shortly before 5 p.m. local time (6 a.m. ET).

The quake prompted a mass evacuation in downtown Jakarta. There was no sign of any initial damage, CNN producer Andy Saputra said.