MOUNT VERNON, Wash. -- An Interstate 5 bridge over a river north of Seattle collapsed Thursday evening, dumping vehicles and people into the water, the Washington State Patrol said.
The four-lane bridge over the Skagit River collapsed about 7 p.m., Trooper Mark Francis said. There was no confirmation how many people were in the water, but Skagit County Sheriff's Department said three people have been rescued from the water and were being transported to hospitals.
It also was not known what caused the collapse of the bridge about 60 miles north of Seattle in Skagit County, which stretches from the North Cascades National Park to a cluster of islands off the Washington coast.
Xavier Grospe, 62, who lives near the river, said he could see three cars with what appeared to be one person per vehicle. The vehicles were sitting still in the water, partially submerged and partly above the waterline, and the apparent drivers were sitting either on top of the vehicles or on the edge of open windows.
"It doesn't look like anybody's in danger right now," Grospe said.
Helicopter footage showed several rescue boats at the bridge collapse scene with several ambulances waiting on the shore. One rescue boat left the scene with one person strapped into a stretcher.
A damaged red car and a damaged pickup truck were visible in the water, which appeared so shallow it barely reached the top of the car's hood.
Crowds of people lined the river to watch the scene unfold.
Multiple witnesses reported seeing a large semi-truck with an oversized load cross the bridge and hit it before the bridge collapsed.
"I saw it. I was less than 50 feet away from the truck when it hit it," said Dale Ogden, witness. "I had just passed it in the fast lane southbound and it was an oversized load."
The bridge is not considered structurally deficient but is listed as being "functionally obsolete" - a category meaning that their design is outdated, such as having narrow shoulders are low clearance underneath, according to a database compiled by the Federal Highway Administration.
The bridge was built in 1955 and has a sufficiency rating of 57.4 out of 100, according to federal records. That is well below the statewide average rating of 80, according to an Associated Press analysis of federal data, but 759 bridges in the state have a lower sufficiency score.
According to a 2012 Skagit County Public Works Department, 42 of the county's 108 bridges that are 50 years or older. The document says eight of the bridges are more than 70 years old and two are over 80.
Washington state was given a C in the American Society of Civil Engineers' 2013 infrastructure report card and a C- when it came to the state's bridges. The group said more than a quarter of Washington's 7,840 bridges are considered structurally deficient of functionally obsolete.
Traffic on I-5 has halted in both directions and backups were significant. Southbound traffic was being diverted to SR 20 while northbound traffic was being diverted to the East College Way Exit.