LOMBOK, (Xinhua) -- A magnitude 6.4 earthquake on Sunday (Jul 29) struck the Indonesian island of Lombok, a popular tourist destination, and was quickly followed by an aftershock, the US Geological Survey (USGS) said.

The quake, which struck at 6.47am on Sunday, was followed less than an hour later by an aftershock of magnitude 5.4 in the same area, the USGS said.

The epicenter's location was revised to 30.7 miles (49.5km) northeast of the island's main city of Mataram. The tremor was only 4.35 miles deep (7km), a shallow depth that would have amplified its effect.

The earthquake was on land and did not trigger any waves or tsunami.