SEATTLE (AP) _ A powerful earthquake rocked the Northwest on Wednesday, shattering windows, showering bricks onto sidewalks and sending frightened people running into the streets of Seattle and Portland, Ore.
At least 25 people were injured.
The strongest quake to hit Washington state in 52 years shut down the Seattle airport, knocked out power to hundreds of thousands of people, cracked the dome atop the state Capitol in Olympia and briefly trapped about 30 people atop a swaying Space Needle in Seattle.
``Everyone was panicked,'' said Paulette DeRooy, who scrambled onto a fire escape in a Seattle office building. The magnitude-6.8 quake hit at 10:55 a.m. and was centered 35 miles southwest of Seattle, according to the National Earthquake Information Center in Golden, Colo. It was felt in British Columbia and parts of Oregon 300 miles away. Buildings in downtown Portland swayed for nearly a half-minute.
``I thought a car had hit my building,'' said Sam Song, who owns a restaurant in Everett, 30 miles north of Seattle. ``Then the ground started moving around.'' Twenty-five people were treated at Seattle's Harborview Medical Center, four of them for serious injuries, a spokeswoman said. There were no other immediate reports of injuries from around the region.
Screams erupted at a Seattle hotel where Microsoft founder Bill Gates was addressing an education and technology conference. He was whisked away as his audience bolted for the exits. Some people were knocked down by others trying to get out. Overhead lights fell to the floor. There was damage to a number of other buildings, mostly minor cracks and broken glass. Bricks fell from the top of Starbucks headquarters onto cars parked below and piled up on sidewalks of the popular Pioneer Square neighborhood, the scene of Mardi Gras celebrations the night before.
Mayor Paul Schell said city crews were examining buildings for safety. He said preparations and seismic remodeling had paid off. ``I think the city has been very mindful of earthquake risks,'' Schell said. ``We have no catastrophic damage.''
Schools throughout the region halted classes, but many served as shelters for children until they could be reunited with parents. Many businesses, sent their workers home. Boeing, the region's major private employer, closed its Seattle-area factories until Thursday.
The Space Needle _ a landmark dating from the 1962 World's Fair that was built to sway during an earthquake or strong winds _ was closed for 2½ hours. None of those stranded at the observation deck and restaurant on top were injured. U.S. Highway 101 buckled in places northwest of Olympia, and another road nearby was closed by a mudslide. Engineering crews were checking the Seattle area's many bridges for damage.
Two Amtrak passenger trains with more than 220 people aboard were halted between Seattle and Tacoma while the tracks were inspected. The Seattle-Tacoma International Airport was closed and the tower evacuated, stranding thousands of people. The Federal Aviation Administration halted all flights in and out of the Northwest's biggest city. The air traffic center for Washington and Oregon, near Auburn, Wash., was operating on backup power.
Puget Sound Energy said 200,000 customers in western Washington lost service, but power was expected to be restored by nightfall. In Olympia, about 10 miles from the epicenter, legislators, state workers and visiting schoolchildren streamed out of the damaged Capitol. ``The chandelier started going and the floor started shaking,'' state Sen. Bob Morton said.
``Someone yelled get under the table and so we did.'' Cracked plaster, gilt and paintings fell from the walls. There was fear the dome would collapse and people linked hands as they walked down the marble stairs of the building. ``If that rascal had tumbled down, it would have been all over,'' Morton said.
The panic was similar in Salem, Ore., where the House and the Senate were in session. ``The building swayed and I yelled, `Earthquake!' and jumped under a doorway,'' said Jon Coney of Gov. John Kitzhaber's office. In downtown Portland, about 140 miles from the epicenter, the Multnomah County Courthouse was evacuated and employees were gathered across the street while officials inspected for damage.
``Everything was shaking,'' said Michelle Noonan of suburban Lake Oswego. ``It knocked over a wood pile outside the house. Books fell off the shelf.'' Earthquake magnitudes are calculated according to ground motion recorded on seismographs.
An increase in one full number _ from 6.5 to 7.5, for example _ means the quake's magnitude is 10 times as great. A quake with a magnitude of 6 can cause severe damage, while one with a magnitude of 7 can cause widespread, heavy damage.