A family on vacation was strolling along a street near Glacier National Park when Derick Madden plowed into them. Madden exited his vehicle, pulled out a shotgun and opened fire, killing 39yearold David Siau and his 18monthold daughter, McKenzie. Madden used to date Christina Siau, who was with the family at the time of the attack. When he ran out of ammo, he pulled out a knife and started stabbing Christina. She was able to kill Madden, apparently with his own knife.