Wire the thing up to a live DC current, when you hear the "AAARRRRGGGHH" and find them still attached to the live metal, bray them off with something wooden as not to get a shock yourself, maybe something you could take a run up with..... After all your saving them from a shock, im sure the police could see that?
Just had my car rifled, Audi A8, took camera activated satnav, Raybans, Recording driving camera, garage fob!!!!! (Immediately changed £65) and a load of cash... Oh and an older I Phone that was tracked to an address close by... Police not found anything yet! However my two pals around 6.3" and 6.4" have narrowed the search down to one of two people..... Only time will tell Eh! I suppose accidents happen now and again, especially on the street.... Scum $H!T BAGS!