The US National Park Service said there had been some deaths but did not have an official figure.
The Pacific Tsunami Warning Center in Hawaii updated its warning to say a tsunami was generated.
Reports from Samoa say two villages were hit this morning while CNN has said a three-metre tsunami had been generated.
A spokeswoman for Samoa Police told Stuff a short time ago that villages on the country’s southern coast had been hit by a tsunami.
"We cannot say much more, we’re extremely busy, but, yes, we have been hit," she said.
Polynesia Radio in Apia told Stuff that they were receiving reports from Siumu and Lotofaga that a tsunami had come ashore.
Both are on the south side of Upolu island, exposed to the area where the earthquake hit this morning.
The Center says the tsunami "may have been destruction along coasts near the earthquake epicentre and could also be a threat to more distant coasts."
The quake struck at 6.48am midway between the two island groups. In Apia, families reported shaking that lasted for up to three minutes. The US Geological Service said the quake struck 35 kilometres below the ocean floor, 190 kilometres from American Samoa and 200 kilometres from Samoa.
The Pacific Tsunami Warning Center issued a general alert for the South Pacific region, from American Samoa to New Zealand. It said there were indications a tsunami wave could be "destructive" along some coastlines.
(dont know how to do the blue box thing)