I'd like to bring the following post on Groundspeak's UK Forum in regards to Cache Trashers

Caches and Trackables being stolen or vandalised, What you can do about it

Please note that we still ask that such incidents are not discussed in public forums. As it has been confirmed that, at least one person involved Trashing caches. Has been monitoring at least the GC Forums.

Deceangi Volunteer UK Reviewer Geocaching.com