Terminating tenancy scam

Hey, just wondering if anyone can help me out. Today I had a visit from a person who claimed to be part owner of the flat im renting, they got the name right. They said that they basically wanted to terminate my tenancy agreement 6 months early and not to go through the estate agent, just through them due to personnal issues, Now this obviously sounds suspect but i just wondered if anyone else has heard of this scam and can help me out. My initial reaction is to say no and that im contracted for another 6 months. Can they terminate my tenancy early legally? Also if i do stay, is there much chance of seeing my deposite again? thanks for you help.

Regards