A two-vehicle crash on Deception Pass Bridge backed up traffic for hours in both directions of Highway 20 Friday morning.

At approximately 9:30 a.m., a late-model Ford Mustang convertible traveling northbound on the highway drifted over the center line and collided with a semi truck near the mid-span of the bridge.

It took firefighters about five minutes to extricate the man in the Mustang, said Marv Koorn, chief of Island County Fire District 2.

Although dispatched as a vehicle fire, neither vehicle was on fire. Koorn said the Mustang’s radiator punctured and caused steam to billow from the car.

The 24-year-old man was transported to Island Hospital in Anacortes and later airlifted to Harborview Medical Center in Seattle. He was listed in serious condition Friday afternoon.

The driver of the truck was not injured.

Washington State Patrol Sergeant Don Ney wouldn’t speculate on the factors involved in the crash.

“It’s under investigation and it’s real early in the investigation,” Ney said at the scene.

He added that the driver of the truck is the only witness to the crash. Other people walking on the sidewalk at the time of the crash didn’t see the initial collision.

The accident blocked one lane of Highway 20. The highway was closed for about an hour when one lane was opened for alternating traffic. The accident caused gridlock stretching miles down the road. By noon, the northbound backup reached De Graff Road.

Firefighters from Fire District 2, Whidbey Island Naval Air Station and Mount Erie Fire Department responded to the accident, Koorn said.

You can reach News-Times reporter Nathan Whalen at nwhalen@whidbeynewstimes.com or 675-6611.