Prosecutors are considering a move to push for an increase to the sentence given to the killer of a teenage student.

Paul Knappett was last week jailed for sixteen-and-a-half years for stabbing to death Kimberley Bage.

But the Crown Prosecution Service (CPS) is seeking advice from barristers involved in the case over the prospects of an appeal.

Knappett, 30, will be eligible for parole after 15 years and 313 days because of the time he has spent on remand since his arrest for the killing in April.

Sixteen-year-old Kimberley's family reacted with anger when his sentence was announced by Mr Justice Field at Teesside Crown Court on Monday of last week.

Since then, senior barristers have been instructed to examine the case to see if there is scope for appeal on the grounds that the sentence was "unduly lenient".

Last night, a spokeswoman for the CPS on Teesside said: "We have written off for advice on it but we have not received an answer yet. We should hear in the next day or two."

Drug-addict Knappett sneaked into Kimberley's family home on the Central Estate in Hartlepool and stabbed her at least 22 times as she slept downstairs on a sofa in the early hours of April 15.

A motive for the killing has never been established, but the unemployed factory worker knew the teenager's family, and her mother because he regularly bought drugs from her.

He was caught after he made confessions to his family, and they contacted police and provided them with the blood-stained clothes he had been wearing.

Knappett had initially denied murder on the grounds he could not recall the attack because of the cocktail of drugs he had taken in the hours leading up to it.

But he changed his plea after a medical expert accepted the amphetamine and valium could have made him violent and left him with memory loss.

Kimberley, who hoped to become a social worker, had been given the keys to her own flat and was poised to move in when Knappett brutally murdered her.

Distraught mother, Paula Hanley, said after the case: "Knappett may have been sentenced to life, but the reality is that one day he will be released from prison.

"Our family are condemned to a life sentence from which we will never be free."

Mr Justice Field based his ruling on a starting sentence of 15 years - adding time for aggravating features and taking time off for mitigating factors such as Knappett's guilty plea.