A Cambridgeshire rape investigation will be the focus of the first episode of the latest series of 24 Hours in Police Custody which airs on Monday (March 11).

The BAFTA-nominated Channel 4 series returns this month and delves into complex and challenging cases dealt with by Bedfordshire and Cambridgeshire.

Monday’s episode will follow a Bedfordshire rape case and the investigation into a stranger rape and sexual assault in Peterborough in September last year.

Investigations by the Bedfordshire, Cambridgeshire and Hertfordshire Major Crime Unit began after a 24-year-old woman was raped by a teenager near Rhubarb Bridge in the middle of the day on September 30.

The teenager threatened the woman with a knife before demanding she went into nearby bushes where he raped her.

The boy left DNA on the woman but detectives found no match on the national system.

Almost a week later, on October 6, a 19-year-old woman was walking close to the same area when she was sexually assaulted by a teenage boy, who smacked her bottom and took her handbag.

Officers carried out extensive enquiries in the area, including intelligence work to try and identify a pool of individuals who matched the physical description and with the relevant behaviour traits.

This included researching all street robbery and theft from persons over the previous 12 months, and it was this research that identified a teenager who had been voluntarily interviewed for a street robbery August 2017.

His DNA was not taken at the time, but when officers visited him he consented to an elimination sample being taken, and this provided the match against the rape sample.

In November a jury found the 16-year-old boy, who cannot be named for legal reasons and was not fit to stand trial, did commit the rape and sexual assault.

He is awaiting sentencing and currently the subject of a hospital order which is due to be reviewed next month.

DCI Adam Gallop, who led the investigation, said: “This was a complex case which was devastating for the victims, who both showed courage and strength throughout.

“Monday’s programme really demonstrates our commitment to doing everything we can to ensure rape offenders are found and the public are protected.

“The rape victim from the case agreed to take part in the programme and gives a first-hand account of the impact it had on her. I hope her story inspires others to contact us if they are victims of similar offences.

“When DC Denise Brown called her to say we had charged someone for her case she said it was one of the happiest days of her life; for me that really captures why we became officers - to make a positive difference when the public have been through truly horrendous experiences.

“I hope this programme provides the public with an insight into the work we dedicate to protecting the most vulnerable while targeting our most dangerous criminals.”

Tune in to Channel 4 for 24 Hours in Police Custody at 9pm on Monday (March 11).