A car which is thought to have been stolen crashed into a level crossing after failing to stop for police.
The Vauxhall Corsa smashed into barriers in Langworth, Lincolnshire, at about 14:30 GMT.
Its driver was airlifted to hospital, while other occupants inside the car suffered less serious injuries, police said.
Damage was also caused to a residential building, but the crash did not involve a train, officers added.
Motorists have been advised to avoid the area.