A Norfolk detective was responsible for providing those hunting for Peterborough serial killer Joanna Dennehy the 'golden nugget', it has emerged.

Earlier this year Dennehy was ordered to spend the rest of her life in prison for murdering three men before randomly selecting and attempting to kill two others.

Mr Justice Spencer told Dennehy she was 'a cruel, calculating, selfish and manipulative serial killer' as he sentenced the 31-year-old at the Old Bailey.

Dennehy, who laughed and smirked as the judge delivered his sentencing remarks, pleaded guilty at an earlier hearing to the murders of Lukasz Slaboszewski, 31, Kevin Lee, 48, and John Chapman, 56, in and around Peterborough over a 10-day period last March.

Police launched a nationwide hunt to find her after the bodies were discovered in remote ditches in Cambridgeshire but she went on to drive 140 miles to Hereford where she repeatedly stabbed two dog walkers.

But it has since emerged that Norfolk police played a key part in helping to track down the killer and bring her reign of terror to an end.

Detective Chief Inspector Martin Brunning the Bedfordshire, Cambridgeshire and Hertfordshire Major Crime Unit, told last night's BBC Crimewatch programme that it was a detective from Norfolk who provided the investigation with key information about the car used by Dennehy and one of her accomplices Gary Stretch.

He said: 'A detective in Norfolk was reviewing a theft at a petrol station and gave me that critical missing link - the registration of the green Vauxhall Astra and that was the absolute golden nugget.'

Det Chf Insp Brunning told Crimewatch the key information had come after he had taken the 'difficult decision' to put out photos of the pair in the media as he believed Dennehy and Stretch were involved in the murder of Mr Lee and together were 'particularly dangerous combination'.

Dennehy, of Orton Goldhay, Peterborough, also admitted two counts of attempted murder and preventing the lawful and decent burial of her murder victims.

The trial of her accomplices, Gary Stretch and Leslie Layton, at Cambridge Crown Court earlier this year, heard that Dennehy had 'cast a spell' over some of her victims.

Stretch, 47, of Riseholme, Orton Goldhay, Peterborough, thought to be Britain's tallest serving prisoner at 7ft 3in, was found guilty of the attempted murder of Robin Bereza and John Rogers after helping Dennehy select her victims in Hereford.

He was also convicted of three counts of preventing the lawful burial of a body at the trial at Cambridge Crown Court.

The judge ordered him to serve life in prison, with a minimum term of 19 years.

Layton, 36, of Bifield, Orton Goldhay, was found guilty of preventing the lawful burial of two murder victims and perverting the course of justice. The judge ordered that he serve a total of 14 years in prison.

A third man, Robert Moore, 56, of Belvoir Way, Peterborough, pleaded guilty to assisting an offender.

Moore was sentenced to three years, after the court heard it had taken 'courage' for him to admit his role in providing accommodation to the killer for two nights.