Three people were injured when the car they were in left the road and hit a tree in Corby.
The accident happened on Wednesday, June 11, at about 7.55pm.
Derbyshire, Leicestershire and Rutland air ambulance attended the accident and one of the people injured was airlifted to University Hospital in Coventry.
A spokesman for the service said: “Northamptonshire police and two ambulances from East Midlands Ambulance Service (EMAS) were first on the scene.
“All three patients were assessed for their injuries. One patient, a 34-year-old man, had suffered suspected chest injuries in the collision. He was given advanced pain relief before being immobilised and airlifted to University Hospitals Coventry & Warwickshire for further treatment. The crew landed at the hospital at approximately 8.50pm.
“The other two patients were treated at the scene by EMAS and the current condition of all patients is unknown.”