Three people needed first aid after a SUV and car collided near a junction.
The incident happened on the Durham-bound side of the A690 at Rainton Gate, near West Rainton, and involved a Nissan X-Trail and a Mercedes car.
Two women and a man were checked over by paramedics after sustaining minor injuries and described as "walking wounded."
Two other men, who had also been inside the vehicles, were uninjured.
Firefighters from Durham arrived to find all five had already got out without the need for help.
The crew ensured the damaged vehicles were made safe and cleared the road of debris.
The emergency services were called to the scene following the collision at 6.40pm yesterday.
The firefighters had been out answering a call to false alarm incident in Durham, where a smoke detector went off in student accommodation, when they were sent to the collision.