While driving in a tunnel you were forced to bring your vehicle to a halt due to a fire. What should you do now?

When you stop in a tunnel due to a fire, your immediate priority is safety and preventing the fire from spreading. Triggering the fire alarm at the emergency call point alerts all tunnel users and emergency services, enabling a quick response and evacuation if needed. Trying to extinguish the fire as best you can helps to control the situation until professional help arrives. Locking your vehicle is not appropriate because it can delay evacuation and emergency access. Therefore, the correct actions are to trigger the fire alarm and attempt to extinguish the fire safely.