Teacher Paul Tramontini, who went on the run with a 15-year-old schoolgirl, was described by a judge as every parent's nightmare as he was jailed for 18 months.

Tramontini, 34, of Ron Golding Close, Malmesbury, triggered a massive hunt when he disappeared with former pupil Katherine Baillie, now 16, in April 2000.

Tramontini had pleaded guilty to a charge of abduction and another of perverting the course of justice at a previous hearing.

Judge David Selwood, sitting at Portsmouth Crown Court on Tuesday, said a custodial sentence was an essential deterrent to stop other teachers from doing the same thing.

He said: "You were in a position of trust and also in a position of power and this offence represents a gross breach of that trust.

"It is said that you had genuine feelings for this young lady and there is genuine emotional attachment between you which has developed over a period of months. This should not have been allowed to develop."

The judge added: "The public will expect a degree of deterrent in the sentence today because you are every parent's nightmare."

Tramontini was sentenced to 18 months in jail after statements from both Katherine and her adoptive parents, Margery, 64, and Tom, 65, were given to the judge.

The courts heard Tramontini met Katherine when she was 14 and a pupil at Mayfield Secondary School in Portsmouth where he taught maths.

Their relationship developed after Tramontini watched Katherine playing in a band but the relationship was never accepted by the teenager's parents.

In April last year Katherine disappeared from home for four days. Later that month, as her relationship with her parents deteriorated, she packed her suitcase and ran shoeless from her home to Tramontini and together they went on the run for 415 days.

The court heard that extensive police searches followed, including appeals on Crimewatch UK. On June 16 this year the couple returned to Portsmouth and Tramontini gave himself up to police.

Robert Duvall, defending, said Tramontini was a hardworking, caring man of good character.

He said the relationship developed at a time when Katherine was taking drugs and drinking alcohol.

Mr Duvall said when Katherine left home on April 26, Tramontini felt he could not abandon her because he felt she was vulnerable.