An ambulance was involved in an accident with a car as it was travelling to an emergency call out.
The collision happened on Sunday evening in Bourne End Lane, Hemel Hempstead, close to The Complete Outdoors shop.
No-one was hurt and no medical assistance was required.
An East of England Ambulance Service spokesman said: “The ambulance was on its way to a blue light call in Borehamwood.
“A rapid response vehicle attended and another ambulance was sent to treat a man in his 60s who was unconscious but breathing.”