Indonesia ? A powerful earthquake hit the western coast of Indonesia’s Sumatra island today, prompting authorities to temporarily issue a tsunami alert.

The quake with a preliminary magnitude of 6.2 struck nearly 100 miles off the coast of the town of Bengkulu, according to the U.S. Geological Survey. It hit about 20 miles beneath the ocean floor, the USGS said.

There was no sign of large waves on the beach and authorities lifted the alert an hour later.

A series of powerful earthquakes in the same region last month killed 23 people and damaged or destroyed thousands of buildings.

There were no immediate reports of deaths, injuries or damage from today’s temblor.