A 50-year-old woman was flown to hospital by air ambulance after a serious crash on the A14 at the weekend.
The incident happened one mile west of junction 1 on the westbound carriageway on Saturday (June 2) at 9.30am.
A Northamptonshire Police spokesman said: “For reasons yet unknown, a grey Toyota Corollas lost control and overturned into the nearside hedgerow, trapping the woman driving the car. There were no passengers in the car.
“The 50-year-old woman, from Cambridgeshire, was released by the Fire Service and flown to Walsgrave Hospital in Coventry by Air Ambulance, where she is being treated for serious injuries.
“No other vehicles are believed to have been involved in the collision which left the carriageway closed for around 45 minutes.”
Witnesses or anyone with information is asked to call the Drivewatch Hotline on 0800 174615.