The roll-over occurred in Batley
A worker was rushed to hospital after becoming trapped under a forklift truck at the side of the road in Batley.
An air ambulance was called to the scene after the forklift rolled over, trapping one person.
An ambulance and a rapid response vehicle also responded to the reports.
Reports suggest workers had been unloading the lorry at the side of the road when the accident occurred.
Further details of the cause of the accident and the identity of the injured occupant have not yet been released.