Without any emotions coming into it, the stuff they took maybe should have been 'better secured' in the first place. There are no 'nice areas' any more, there are scum who are a waste of food, and have no right to be alive, everywhere.
Oops...that last bit sounded a bit emotional.
Short of parking them in the kitchen, probably as secure as reasonably possible - brick built "shed" (more like a garage) with multiple locks.
Its not the first time, and doubt it will be the last, for either Mum or little bro. And Mum has had the house done before as well. I suspect the they had eyed up previously, as they seemed to know where stuff was, and where the cameras were.
I too believe in shooting them, along with any do-gooder who says otherwise. We all have to do honest work, why do some feel they shouldn't have to.
As for prison HTK, nah, a bullet is cheaper, and fully resolves the issue.