An ambulance and a semi-trailer collided at an intersection near Campbelltown this afternoon, with two paramedics airlifted to hospital.
The crash occurred before 3pm at the intersection between Narellan Road and Mount Annan Drive, a police media spokesman said.
The NSW Ambulance vehicle was responding to a triple-zero call at Mount Annan.
The ambulance was left on its side with two paramedics trapped inside, one for about 30 minutes and the other for about 40 minutes.
A male paramedic was airlifted to Liverpool Hospital in a stable condition, with a head injury and other minor injuries, a NSW Ambulance spokesperson said.
A female paramedic was airlifted to Westmead Hospital with back and neck injuries. She was also in a stable condition.
The truck driver and a child passenger were assessed at the scene but not taken to hospital.