Activation Lock.

Hi!

A couple of weeks ago I found an iPhone 6 at my college and handed it in at the local police station. The officer said if no one claimed it within a week or so I could keep it. The iPhone was never claimed and I got a call to come get it. When I went to start the phone I was greeted with Activation Lock screen. Is there any way to fix this and or remove the account from the phone? I'm guessing calling apple wouldn't help as I have no proof of purchase so I don't know what to do! Any help would be great.