PORT MORESBY, Papua New Guinea >> A powerful earthquake shook Papua New Guinea’s northern coast, and disaster authorities haven’t been able to contact residents of a small town near the epicenter.

It’s possible they headed to higher ground as soon as they felt the earthquake and were not immediately reachable, said Chris McKee, the assistant director of the Geophysical Observatory in the capital, Port Moresby.

The shallow, magnitude-6.8 earthquake struck about 11 miles east of the small town of Aitape on Wednesday morning (Tuesday afternoon in Hawaii.) McKee said there were no reports or indications of a tsunami.

The Pacific Tsunami Warning Center said there was no widespread threat of a tsunami based on historical data, but a quake of this strength had the potential to generate localized tsunamis within 62 miles of the epicenter.

He said people in the town of Vanimo, about 145 kilometers (89 miles) from the epicenter reported they had felt the quake strongly. There were no initial reports of damage or injuries.

The U.S. Geological Survey said the quake was at a depth of 8 miles. Shallow quakes can potentially cause more damage at the surface. 

Papua New Guinea is prone to seismic upheaval due to its location on the Pacific “Ring of Fire,” an arc of volcanoes and fault lines encircling the Pacific Basin. 

A 1998 magnitude-7.0 earthquake on the northern coast generated a large tsunami which swamped Aitape and several other villages, killing about 2,200 people.