Mmmm. This is not a police matter. The damage was accidental or thats what he would say.
There is a part to the criminal damage legislation that states that if the person was reckless then that would be criminal but this does not count here. (For example, a person throws a brick and does not care where it ends up. The brick smashes a window that is not his, get it?)
I suppose its a course of going through the civil court.
Sorry mate.
DC.