Papua New Guinea authorities are assessing the extent of damage from a powerful earthquake that rattled coastal towns the previous evening.

The magnitude 7.5 quake struck around 11 p.m. Tuesday, according to the U.S. Geological Survey. It was offshore about 45 kilometers (28 miles) northeast of Kokopo, which has about 26,000 people.

Chris McKee, the acting director of geohazards management, said there was some damage in Kokopo as items were shaken from shelves and the power had been cut. He said a small tsunami was generated, but the late-night darkness made an assessment difficult.

Garfield Tarabu, a spokesman at the National Disaster Centre, said a disaster coordinator was on the ground assessing the situation but they hadn't yet gotten an update on the extent of the damage.