A pedestrian was airlifted to hospital after being hit by a car.
Police were called to the incident at the junction of Eskdaill Street and Montagu Street in Kettering just before 9am on Thursday.
A police spokesman said: “We were called at 8.55am to a collision where a man had been knocked over.”
An ambulance attended along with the air ambulance, which landed in Mill Road park nearby to treat the patient who had suffered a head injury.
Police closed a number of roads to allow the air ambulance to land and diversions were put in place.
A spokesman for the air ambulance said a 66-year old man was airlifted to hospital after sustaining head injuries in the incident.
A crew from East Midlands Ambulance Service (EMAS) were first on the scene and assessed the patient for his injuries.
The crew requested the attendance of an air ambulance to provide a rapid transfer to the nearest neurosurgical centre.
Derbyshire, Leicestershire & Rutland Air Ambulance (DLRAA) landed at 9.20am and flew the patient to hospital.
Any witnesses to the collision are asked to call the police on 101.