Parked up next to me, when there were numerous other free spaces. Hit my mirror when opening door to get in. Sarcastically waved and drove away as I got out to inspect it. Scratch is very minor but my partner and I felt very intimidated by them, hence why I wanted to do something about the situation in some small way.
Man, 18-25, group of (5?) guys similar age too.
St Oswalds Retail Park, Gavel Way, Gloucester GL1 2UE, UK