Sort of, Druchii. It's sub-letting, which most tenancy agreements would explicitly state that you (the tenant) cannot do with the permission of the landlord. So it does look as though the guy has not only done a runner with unpaid rent, but also broke the tenancy agreement. None of this much helps you. I would seek legal advice from a housing law specialist. CAB can be good - can be crap though. Very variable.
[edit] Slightly beaten to it by Matt
