A police officer and two people have been stabbed at the scene of a two-car crash on a major southern Sydney highway.
Two vehicles collided about 9am in Engadine on Sunday, with police arriving to find an injured man sprinting from the scene.
The man, who appeared to be suffering stab wounds, was arrested after being tasered, police said.
A male officer suffered a serious laceration to his left wrist, seemingly during the arrest.
Meanwhile, a woman who police understand was a passenger of one of the crashed cars, was found with multiple stab wounds.
A fourth person was also found injured, though their link to the incident was unclear.
All four are being treated by paramedics.
A five-kilometre stretch of the Princes Highway is closed in both directions.Â