A magnitude-7.5 earthquake has struck off the island of Vanuatu in the South Pacific, according to the U.S. Geological Survey (USGS).

The USGS noted that the quake struck at 3:55 a.m. local time on Sunday (12:55 p.m. EDT on Saturday) and was centered 38 miles southwest of the town of Port-Vila at a depth of about 25.2 miles.

About twenty minutes later, a weaker aftershock of magnitude-5.9 was recorded.

Earthquakes of this size sometimes generate local tsunamis that can be destructive along coasts located within a hundred kilometers (80 miles) of the earthquake epicenter, said The Pacific Tsunami Warning Center.

Vanuatu is an archipelago about 1,100 miles east of northern Australia. It is located in one of the most seismically active parts of the world.

There are no immediate reports of casualties or damage.