There are many thieves about at the moment.
One soloution to this problem is vigilance and to let them know we are onto them. If you see suspicious activities or shifty people, please alert staff, warn those in the building to look after thier stuff and maybe casually follow them around so they know we are watching them. Ask suspicious people if you can help them, let them know we are watching. Look after each other.
Please always gaurd your belongings and if you can think of other soloutions, let us know.