A bus driver was hit by a metal bar that smashed through the window.

Stewart O'Leary was manoeuvring on I-405 to transport the North Creek High School girls' basketball team to a game when he was suddenly struck by a metal bar to his chest in Bellevue, Wash., on February 13.

Onboard CCTV footage shows Stewart screaming in pain upon impact as he navigates the freeway.

Two coaches next to him were alerted and immediately walked toward him to help pull over the vehicle, while the other called 911 for emergency assistance.

The teachers managed to help slow the vehicle on the roadside.

Local reports said that the metal bar flew through the windshield, shattering the glass and hitting Stewart with shards to his face.

Stewart, who is now recovering from the accident, said: 'It was instantaneous, it was violent. I could see the slice in the windshield, so I got the idea something came through it and hit me. I was covered in glass.

'I'm glad it was me, and not any of the passengers.

'I knew I was going to be ok. It certainly could have gone another way. In fractions of a second, things can change.'

Stewart was transported to a nearby hospital and treated for a serious bruise to the chest and glass shards that hit his face.

Washington State Patrol troopers said they have not been able to determine where the piece of metal originated.