'I knew it was coming': Mobile phone footage captures shocking crash

A man in the US who captured a shocking car crash on his mobile phone has revealed he knew the moment of impact was coming long before it happened.

Kaecieo Bass and his colleague Kevin Denney were travelling along Pennsylvania's Route 21 near Fayette County earlier yesterday when they spotted an erratic driver ahead, Channel 11 WPXI reports.

Fearing the worst, Mr Bass began recording from the passenger seat.

"I don't know if she's drunk or what's going on," Mr Bass says in the video.

"They need to get their mind right. I hope nothing happens to them."

The pair continue to film as the car swerves into opposite lanes of traffic, forcing approaching vehicles to retreat to the road's shoulder.

"I hope they're not falling asleep. Please put a hand of protection on that car, father God," Mr Bass says.

As the erratic driver goes to make a turn across traffic, she cuts off an oncoming car and the pair filming the incident are thrust into harm's way as parts of the two cars spray across the road.

Luckily, no one was seriously injured in the crash.

According to police, the offending driver had just worked a midnight shift and fell asleep behind the wheel.

It is expected she will be charged with minor traffic violations following the smash.