A Whidbey Sea-Tac shuttle bus was involved in a five-car accident late this afternoon that caused a lengthy backup of traffic on Interstate 5 in Lynnwood.

Trooper Keith Leary with the Washington State Patrol, who was on scene, said only one of the six people on the bus suffered a minor injury, but it wasn’t serious enough to warrant a ride to the hospital.

In all, four people received minor injuries; two of those were transported to the hospital by ambulance.

Langley resident Richard Bacigalupi was caught in the five-mile backup of traffic following the 4:35 p.m. accident near the exit at 44th Avenue W. He said the front of the shuttle bus was “smashed in” and a pickup truck was upside down in the road.

According to Leary, the accident occurred as the bus was headed north to Whidbey Island. It appeared, he said, that traffic slowed in front of the bus, but the driver didn’t stop in time. The bus struck the vehicle in front of it, setting off a chain-reaction accident involving five vehicles, the trooper said.

Leary said the bus passengers would be on their way as soon as the replacement bus arrived.