Parasites mate.
We've got a few pikey camps around, it's likely to be them.
I do know a few people who know a few elders, but I'm not holding my breath.
Good for your mate, I hope he gave him a good talking to?
Scumbags.... Happened in Summer to a mate, he put an advert on Facebook and offered a reward, but other anglers also looked out for it, 1 guy even found out who had most of his gear and broke into (well smashed his door in) flat for it all back.