What would you do if a man yelled at your daughter and broke her phone?

Let's say you have a 13 year old daughter who went to a boy band ( 4 town concert) your daughter and her friends managed to sneak behind the stage and take pictures of one of the performers without him knowing ( let's name him Dustin) when Dustin sees her and her friends, he freaks out. He grabs her phone, smashes it then screams and yells at the girls until a couple of them started crying.

He called the girls disrespectful little shits and said you don't know how to parent. Her phone was also destroyed and your daughter came home crying.- what would you do?