tenant in prison

Possession - Section 8 and Section 21

tenant is on a shorthold agreement dated 11/12/10. he is in prison i have tried every means of contacting him, he has a sister but her phone number no longer exists. he has not contacted me in any way.his rent should be paid on 18th nov, by housing benefit i do not think it will be paid because he wont have signed on. i would like him to leave the property mainly because he has been put in prison for causing criminal damage to a property where a girl works whom he has been stalking, this has been going on for around 3 years. i want him to leave to get away from her and to protect my other tenants and my property. can you advise on the eviction notice please.