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

In the event of a fire in a tunnel, the correct response involves both triggering the fire alarm at the emergency call point and attempting to extinguish the fire as best as one can. According to German traffic regulations, it is critical to alert authorities to the danger immediately to ensure that emergency services can respond quickly.

Additionally, while trying to extinguish the fire, it's important to attempt to mitigate the situation and prevent further hazards, like smoke or spreading flames, especially in such a confined space as a tunnel. Locking your vehicle is not appropriate in this context because the priority should be on safety and alerting others rather than securing the vehicle.

Thus, the combination of choices 1 and 2 is necessary for effective emergency response and aligns with the principles of safety and urgency outlined in traffic laws.