A magnitude 7.9 earthquake shook the Pacific Ocean near American Samoa - an island in the South Pacific archipelago - today generating tsunami waves, U.S. government agencies said.

A tsunami warning was released for American Samoa, Samoa, Cook Islands, Tonga and Fiji, while a tsunami watch was issued for Hawaii and Papua New Guinea.

The islands are located in the Pacific Ocean at the east of Australia.

The United States' west coast along California, Oregon and Washington was not issued a tsunami warning but officials forecasted that a much decreased wave could reach Hawaii at 7:18 p.m. EST, according to CNN.

The epicenter of the quake was located 120 miles southwest of American Samoa at a depth of 11.2 miles.