A desperate mother fears her 13-year-old daughter, who has been missing from home for almost two weeks, may be being kept against her will.

Sinead Howard went missing on Saturday, September 18, just days after celebrating her mother's birthday with her.

Mum Noeleen Duffy, 42, has tried ringing her daughter's mobile phone but each time it is answered by another girl.

She said: "Every time I ring I can hear her in the background asking who it is but this girl won't put her on the phone.

"I think Sinead is either too frightened to speak to me or someone is not letting her. I think she is being kept against her will."

Sinead lives with her mother and brothers Glenn, 24, and Kevin, 21, in South Field Avenue, Odsal, but was staying with her grandmother, Ellen Duffy, 65, at her home in St Paul Avenue, Wibsey, when she disappeared.

Tearful Mrs Duffy said: "There was no reason for her to go. Everything was fine.

"A few days earlier we had a celebration for my birthday with a few friends round. But she got up on the Saturday, told her gran she would be back later and we haven't heard anything since.

"I just want her back home safe.

"All her friends at school have been ringing and are waiting for her to come back.

"The police said they were following up inquiries and going through addresses."

Sgt Aidan Hodgson, of Odsal Police, said they were "very concerned" for Sinead's welfare.

He said: "Due to her age she is classed as very vulnerable, and because of the length of time she has been missing and the fact there have been no sightings or reports of her. All missing people are graded on their level of vulnerability and an officer has been allocated to the inquiry round the clock. We have several mobile phones listed that she could have in her possession. They are being checked but we have not spoken to Sinead."

Sgt Hodgson said checks were being made at hospitals and places Sinead had frequented before. Inquiries were being made to try to make contact with known friends and associates of the teenager, who has been missing before.

Sinead is white, with blue eyes and mousy brown hair tied back. When she disappeared she was wearing a black crop top, light blue jeans, pink shoes, a black jacket and gold ear rings.

Anyone who knows of her whereabouts is asked to contact PC Kirstine Bell on (01274) 376459.