A deputy has been suspended after a motorcyclist was killed during a chase, in which the law enforcer twice crashed into the bike, sending the rider to his death.

Dashcam footage from the deputy's car shows the vehicle strike the motorcycle, which was being driven by Robert Lee Clark, Jr, the Daily Mail reports.

The 30-year-old died at the scene of the collision in Berkeley County in South Carolina.

Deputy James Vansant's cruiser was travelling at speeds of around 90mph before the crash, and the sheriff's office has said Mr Clark died because the bike was in the wrong gear, RT reports.

Advertisement

Officers found cannabis on his person after the crash, which happened last Wednesday.

A statement from the department said Vansant has been placed on administrative leave while an internal investigation is carried out.

Vansant said he was looking for speeding vehicles when he saw Clark's motorcycle doing 106km/h in a 72km/h zone.

The eight-mile chase saw the motorbike reach speeds of up to 178km/h.