Tenant with psychotic problems

Tenancy Types and Management

I let a flat to a gentleman who suffers bi-polar disorder and is in receipt of psychiatric care from our local mental health team. He has been with me for about 4 years and receives 6 month shorthold tenancy agreements currently due to expire in March 2007. I have not issued him with a Section 21.

He is displaying horrendous behaviour, causing distress and nuisance to other tenants (3 flats in the building) who are also psychotic, has all night parties, has broken into his electric meter, pulled down fire doors, removed every handle in the flat, cupboards included, leaves the flat open to all and sundry whist in the pub, has a girlfriend who urinates everywhere, gives her his medication which he won't take himself, and is generally very unwell. I have been trying to get psychiatric care for him under the mental health act and wish him to leave his flat, I am unable now to manage him. Can I get rid of this man other than by issuing 2 months notice, and do I understand that because this will be before his 6 months expires in March he can actually stay until then, and if he is sectioned or at least detained under the mental health act, should he be discharged after 28 days do I have to take him back until his tenancy/notice expires. Any help gratefully accepted,
Thanks
Pru