Five people were taken to hospital on Saturday after a head-on car crash on Carvers Road, Oyster Bay about 10.30am.
Police said a Ford Territory 4wd and a Toyota RAV4 collided, leaving a woman trapped in the wreckage of the Toyota for about two hours.
Emergency Services cut the woman free and she was taken to Liverpool Hospital with multiple internal injuries. A child who was in the Toyota was also taken to hospital.
A man and a young woman from the Ford were taken to Sutherland Hospital, and a woman to George Hospital. Police said their conditions were unknown.
Police closed Carvers Road as they investigated. They ask anyone with more information to contact them at Crime Stoppers on 1800 333 000.