Fixed detection cameras - they monitor and record all movements in tunnels and unusual situations in traffic (vehicle stop, pedestrian movement, driving in wrong direction, car accident, fire, smoke, cargo on the road, traffic congestion etc.)
Camera will detect unusual situations and incidents. On operator's monitors there will be an alarm that points to the exact incident site. Operators have pre-set scenarios for reaction.
Detection cameras record all traffic in a tunnel (all movements) and archive it into a database which allows operators to replay certain parts of the video.