PORT MORESBY, Papua New Guinea — A strong earthquake rocked eastern Papua New Guinea on Thursday, causing some damage and plunging parts of the coastal city of Lae into darkness, officials and witnesses said.

No casualties were reported in the South Pacific archipelago nation.

The quake with a preliminary magnitude of 6.7 hit just before 6:48 p.m. local time and was centered about 250 miles north of the capital Port Moresby and 60 miles north of Lae, the U.S. Geological Survey said.

The Pacific Tsunami Warning Center in Hawaii said no tsunami warning was issued.

Larry George, a manager of the City Mission charity hostel in Lae, said the quake was the biggest many long-term residents had felt there.

"It emptied our shelves and smashed glasses," George said, adding that a water tank had burst and the power was cut in parts of the city.

Lae International Hotel staff member Nora Gorogo said television sets rattled off shelves and were smashed in several hotel rooms.

She said she was not aware of any major damage or casualties.

The emergency services in Lae and Port Moresby's disaster management center could not be immediately contacted for comment.

Parts of Papua New Guinea are frequently shaken by earthquakes.