A major quake with a magnitude of 8.3 has struck off the South Pacific island nation of Samoa, triggering a tsunami and killing an unknown number of people in Western Samoa.

At least 36 people were reported killed in American Samoa following the powerful earthquake and tsunami which hit the area Tuesday.

A tsunami was observed at Apia, Western Samoa, and at Pago Pago, American Samoa, according to the West Coast/Alaska Tsunami Warning Center, a branch of the US National Oceanic and Atmospheric Administration.

The waves at Pago Pago reached 5.1 feet above normal sea level, according to the Pacific Western Tsunami Warning Center in Hawaii.

AFP reported that some villages were wiped out.

A local police spokeswoman said the tsunami killed an unknown number of people in Western Samoa. "The tsunami has struck some parts of the country," she told Reuters by phone. Asked if there had been any deaths, she added: "Yes".

An unknown number of people in American and Western Samoa have been killed and people have fled to higher ground, an official of the US National Park Service said early Wednesday.

The US Geological Survey reported that the earthquake shook the waters about 120 miles (190 km) southwest of the remote Pacific islands at 1748 GMT on Tuesday.

Also, the Pacific Tsunami Warning Centre issued a tsunami warning for New Zealand and a number of small Pacific islands.

"Sea level readings indicate a tsunami was generated. It may have been destructive along coasts near the earthquake epicenter and could also be a threat to more distant coasts," the center said in a statement.

A tsunami watch is also in effect for Hawaii, Papua New Guinea, and other small Pacific islands.

In 2004, a powerful quake in the Indian Ocean resulted in a destructive tsunami that killed tens of thousands people in Asia.

ZHD/MD/FTP/JR/HGL