VANCOUVER A magnitude 6.4 quake struck off Vancouver Island on Friday, some 175 miles northwest of Vancouver on Canada's Pacific coast, but no damage was reported in the city, eyewitnesses said.
In the U.S. city of Seattle just south of the border, police reported slight rattling but no signs of damage.
Canada says the Pacific Coast is the country's most earthquake prone region, with some 1,000 tremors a year. There have been about 100 quakes of magnitude 5 or higher off the coast of Vancouver Island.
The quake, initially reported as a magnitude 6.8, was very shallow at 14.3 miles under the seabed, said the U.S. Geological Survey. The Pacific Tsunami Warning Center said the quake did not trigger a tsunami warning.
An eyewitnesses in one downtown Vancouver building said it swayed. Other people in the area said they felt nothing.
Vancouver Island hugs the coast of British Columbia and is almost 300 miles long and some 50 miles wide at its widest point. Much of it is thinly populated, with rocky beaches, thick forests and cliffs falling into the Pacific Ocean.
The quake struck close to the town of Gold River on the island.
"There were three of them (tremors). Two were back to back and then five minutes later there was a third smaller one," said Laurinda Rich, manager of the Gold River Golf Club.
"It shook the whole building here at the golf course. Everything was shaking in the kitchen," she told Reuters.
(Reporting by Greg Joyce and Nicole Mordant in Vancouver, Bill Rigby and Peter Henderson in San Francisco, Janet Guttsman in Toronto; writing by David Ljunggren, Editing by Sandra Maler)