He is not a kid now, he should be responsible for his actions. With all that twitter followers he should know the consequences.
For me, that should've been reported immediately. His followers are young kids, and these kids will believe that he will do no wrong. They must've (actually. obviously) thought that it was a game and the first one to get it correctly wins and gets the chance to talk to him. Poor owners of the phone numbers must've been answering phone calls all night long.
And this is why some people should not be allowed to get a Twitter account.