But if you start a fire, put it out! Unless you plan on going to jail if caught, it's no joke.
When I was in the Army incendiary ammo started fires all the time. They also spread fast, think about all that incendiary mix flying around in the air. It will start fires by landing on everything that likes to burn.
Don't just pack up and run, if someone gets your license plate your done. Make an attempt to put it out, if you can't, call the FD for help. Just remember it was a strange ricochet that started it.
Be safe and be smart. It will only reflect negatively on shooters.