Two people injured when an ambulance overturned on a busy carriageway have been released from hospital.

The private ambulance from the Royal Marsden Hospital in London was travelling north on the A23 at Pyecombe on Thursday when it overturned on the central reservation at about 6.30pm.

The two crew members, a 49-year-old woman and 23-year-old woman, were taken to the Royal Sussex County Hospital in Brighton for treatment. They were discharged from hospital later the same evening.

The ambulance was not carrying a patient. The northbound carriageway was closed for two hours as a result and road policing officers at Haywards Heath are investigating the cause. At this stage police do not believe any other vehicles were involved.

The scene was attended by all three emergency services and highways staff.

A police spokesman said: “Police appreciate the patience of drivers whose journeys were disrupted and are grateful to drivers who came forward at the scene and those who also stopped to assist.

“Anyone who saw what happened is asked to contact Sussex Police via, or by calling 101, quoting serial 1331 of 8/1.”