A woman who stepped in to raise her dead sister's four children as well as her own was injured when her Ford Escort was involved in a collision with a police car.

The accident happened on the A4095 between Bampton and Brize Norton, near Lew Heath House, on Friday, causing traffic chaos.

Bonnie Brooks, of Southby, Bampton, said the police car was first in collision with another car and then her own. She was taken to the John Radcliffe Hospital, Oxford with a suspected broken back, but after tests and X-rays it was found she had no broken bones and was allowed home.

The 34-year-old, who stepped in to raise sister Cathy Newman's four children after she died in May from a blood clot, said: "It was absolutely horrendous. Everything happened so quickly."

The youngest of her own three children, William, was with her at the time and was still shaken, she said.

Thames Valley Police spokesman Paul Anthem said the police car was answering an emergency. He said: "Unfortunately, as the car was going along the main road it appears another car trying to turn right has been in collision with the police car."

A traffic officer will oversee an investigation.