The major link between the US and Canadian sides of the Pacific Northwest region was severed after a bridge collapsed, dumping a handful of vehicles and people into a river, police said. All three people who were on the span were rescued and taken to hospitals.
The four-lane Interstate 5 bridge - more than half a century old - collapsed about halfway between Seattle and Vancouver, British Columbia. Washington State Patrol Chief John Batiste blamed it on a big truck carrying a tall load that hit an upper part of the span. The truck made it off the bridge and the driver remained at the scene and co-operated with investigators.
The collapse came at the start of one of the busiest holiday weekends of the year in the US, Memorial Day weekend. The collapse came before sunset on a clear day.
Dan Sligh and his wife were in their pickup truck on Interstate 5 heading to a camping trip when the bridge before them disappeared in a "big puff of dust."
"I hit the brakes and we went off," Mr Sligh told reporters from a hospital, adding he "saw the water approaching ... you hold on as tight as you can."
Mr Sligh, his wife and another man in a different vehicle were dumped into the chilly waters of the Skagit River. They were injured, but authorities said it appeared nobody was killed in the bridge failure that raised the question about the safety of ageing spans. The three had non-life-threatening injuries.
Mr Sligh said his shoulder was dislocated in the drop into the water, and he found himself "belly deep in water in the truck." He said he popped his shoulder back in and called out to his wife, who he described as being in shock initially as they waited for rescuers to arrive in boats.
Jeremiah Thomas, a volunteer firefighter, said he was driving nearby when he glimpsed something out of the corner of his eye and turned to look. "The bridge just went down, it crashed through the water," he said. "It was really surreal."
The bridge was about 25 feet (eight metres) above the water. Officials said it appeared that two vehicles - a car and the pickup with the travel trailer attached - fell into the river. The water depth was about 15 ft (4.5 metres), and the vehicles half-visible in the water likely were resting on portions of the collapsed bridge.
The bridge was not classified as structurally deficient, but a Federal Highway Administration database listed it as being "functionally obsolete" - a category meaning that the design is outdated, such as having narrow shoulders and low clearance underneath. The bridge was built in in 1955 and had a sufficiency rating of 47 out of 100 at its November 2012 inspection, Transportation Department spokesman Noel Brady said.