AN ACCRINGTON mum has appealed for her missing teenage son to get in touch after he vanished three weeks ago.

Usually, profoundly deaf 19-year-old Christopher Knott informs his family if he is not coming home at weekends from his deaf school in Doncaster, but he hasn't been seen or heard of since 11 September.

His distraught mother, Anne, a carer in a Blackburn home, said: "Every time the phone rings I'm hoping it will be him. His brothers and sisters are all devastated. He has nothing to worry about. We are all really missing him and worried about him, and we just want him to get in touch."

She described Christopher, who is 5ft 5ins tall, as "very shy, timid and nervous" but he has never disappeared before.

Sergeant Christine Driver of Accrington Police said: "We are growing increasingly concerned as Christopher has not been seen for three weeks and is believed to be vulnerable."

Police believe that after leaving Doncaster the teenager withdrew money from a cashpoint in Blackpool. Subsequently there has been an unconfirmed sighting of him in Stoke but his mum, who lives in Willows Lane, said: "As far as I know he doesn't know anyone in Stoke."

Before joining the Doncaster Deaf Trust in January, Christopher studied joinery at Accrington and Rossendale College before moving on to Blackburn College. He left Doncaster with none of his belongings but was wearing a cream coloured Nike top and white Adidas trainers. He is slim with blue eyes and has short light brown hair.

Anyone with information can call Accrington Police on 353721 or the National Missing Persons Helpline on 0500 700700.