A powerful earthquake with a magnitude of 7.7 hit Canada's Pacific coast province of British Columbia late Saturday, setting off a small tsuanmi, but there were no immediate reports of damage, officials said.

The US Geological Survey said an earthquake with a 7.7 magnitude hit the province, centered 123 miles (198 km) south-southwest of Prince Rupert at a depth of 6.2 miles (10 km), the USGS said.

Earthquakes Canada said the quake in the Haida Gwaii region has been followed by numerous aftershocks as large as 4.6. It said a small tsunami has been recorded on a deep ocean pressure sensor.

"It was felt across much of north-central B.C., including Haida Gwaii, Prince Rupert, Quesnel, and Houston. There have been no reports of damage at this time," the agency said in a statement on its website.

British Columbia's emergency info center said a tsunami warning was in effect for the north coast and Haida Gwaii islands, as well as central coast communities like Bella Coola, Bella Bella and Shearwater.

Local media reported that residents in some coastal communities were moving to higher ground, include aboriginal residents in Haida Gwaii.

The quake was not felt in the larger cities of Victoria and Vancouver in the south, a resident in each city told Reuters.

The Pacific Tsunami Warning Center had said no destructive tsunami was expected from the quake but the West Coast-Alaska Tsunami Warning Center issued a warning for coastal sections of British Columbia and Alaska.