i have a similar (non-sign story)
some of my friends went out for cabbage nght (mischief night, the night before halloween) one year, while i was at my gf’s house. they were located near our town pool, with some paintball guns, shooting at passing cars. one car, a large pickup passed by, and got shot up by them. the truck proceeded to stop, spin around, and flash his brights where my friends were, and they promptly ducked down to hide. he drove away. lo and behold, the pickup belonged to my gf’s father (a 6’4" linebacker sized man who has a brown belt in REAL karate (that is, not tiger schulmanns, but an actual dojo)), who came back to her house (where we were) told us what had happened, and proceeded to get the family doberman and drive back to the spot where the car had been shot in order to scare the living shit out of the kids (he wasnt mad, but wanted to fuck with them). fortunately for them, my friends had already moved on. i suspected them as soon as i heard what happened to my gf’s father, and had my suspicions confirmed when i asked them the next day (they were busted later that night by the cops for shooting the paintball gun from a moving vehicle.