There are both events at the end of missions and while you are patrolling in a mission. To find one in a mission, follow the white arrows until one reveals itself. The event is random and will be fixed for the mission even if you dashboard. In the event options, look for ones with a red funeral cross. These options can result in damage or death. There is a RNG factor. If a character from your team does not die, you can dashboard before exiting the event and attempt again. There is a sniper event that tends to be on the lethal side. Just be careful because it is really easy for the game to save its progress and you don't want to find yourself a man down mid-mission (and possibly for the rest of the game).