get yourself some high powered halogen lights with motion sensors,put em by any access points,tell as many nieghbours as you can whats going on,keep your dogs in as much as poss,for a while,be extra vigilant with all strangers calling at the house,if youre that worried get a cctv camera,even a dummy one will help,these are gypos mate,you need to let them see some security going in.im only down the road from you and theres alot of em in this area,hope this helps.
These are arsholes to start with. How one man can nick someones dogs from his back garden is beyond me. I have CCTV which is on