Not a good thing to hear, but a major reason why we travel in converted buses is security, would never open our door until we know who is knocking. When you're camping on the side of the road, it's not those around you you need to worry about, but those passing by who may be opportunists.
I don,t open the door until I know who is there, and I carry a baseball bat near the door.If they give you trouble, call the police.I used to carry a shotgun, but these days only the bat.Its just one of those things when free camping. I hope the cops catch the bastards. Bill
Most unfortunate, however we need to maintain perspective, this is very much an isolated instance.
One of my rules is don't free camp close to towns or built up area's and if possible camp out of sight of the road, what the eye cant see the heart doesn't grieve.