A CHANNEL Four documentary last night cast a new light on the investigation into the disappearance of two boys linked to an Oswestry killer.

'In the Footsteps of Killers' aired on Wednesday night with criminology professor David Wilson joined by actor Emilia Fox to go over the cold case of David Spencer and Patrick Warren, who went missing on Boxing Day in 1996.

Called the 'Milk Carton kids' – as their faces were put on cartons for the first time in the UK – the pair were last seen at a Shell petrol station in Chelmsley Wood, Solihull just after midnight, where an attendant – Ellen Morgan – gave them a packet of biscuits.

The two have never been found – but investigations are ongoing at a site in Solihull. Read more about that here.

Here are the main claims made in the documentary.

  • Field is still the prime suspect – but he denies it

While uncovering more details about the case, Professor Wilson and Fox unearthed evidence that reaffirmed their view that Field – who is currently in jail for the murder of 14-year-old boy Roy Tutill – was and remains the main suspect.

The view was confirmed by Dr Graham Hill, a psychologist who had interviewed Field on a number of occasions, where he blamed alcohol for his offences.

Dr Hill spoke specifically of the Tutill case, and also described Field as a predatory paedophile as well as telling Prof Wilson that he had also interviewed him on behalf of West Midlands Police regarding the boys.

In that interview, Dr Hill said that while he didn’t admit to the abduction, WMP could put him in the vicinity, while he had been drinking and driving a white van.

Dr Hill said there was ‘no better suspect’ for the boys’ murder – but Field still denies their abduction and killing.

  • Field had previously contacted the boys

The presenter said he was not aware of many other offenders who tried to abduct more than one teenage boy on occasions, and it came to light that a statement given by Bob Poole in the investigation of Mark Billington's death – of which Field was also suspected – that Field had previously tried to interact with the boys.

Billington was found hanged near Coventry in 1984.

The petrol station attendant had not noticed any struggle, and in the documentary Prof Wilson posited that this was because the boys already knew Field.

  • The boys' likely whereabouts

The programme also spoke to geoprofiler – somebody who investigates potential sites for bodies – Dr Samantha Lundigran.

She said that they would look at locations that gave Field accessibility to commit the crime and dispose of the body.

The programme ended with the presenters travelling to a wooded area in Solihull which was flagged up as most likely to be where the boys are – in their view ­– by geoprofiling.

  • Claims about Field

Other evidence by Prof Wilson and Fox included suggesting the Oswestry offences that saw Field convicted in 1986 – in which he tried to abduct two other teenage boys, who managed to escape – indicated a pattern of offending.

Another contributor, journalist Leda Reynolds, also pinpointed Field as her main suspect after writing about the case extensively, including her encounter with Field as a fellow local of a pub in Solihull.

It was her dossier that she took to police that finally switched the case advanced from a missing persons to a murder investigation.

  • What do the police say

A statement from WMP on June 10 said: "In the early hours of 27 December 1996, Patrick Warren was reported missing to West Midlands Police. Officers attended Patrick’s address within hours of the report and a missing persons investigation began, this included visiting David Spencer’s address at 4.30am on 27 December 1996 although David had not been reported missing to police at that time.

"WMP completed a large number of enquiries to try and find the missing boys. This included following up enquiries as a result of media campaigns, where CCTV existed this was recovered and viewed and friends of the boys were traced and spoken to.

"This missing person investigation was overseen by an Inspector with staff allocated to the investigation and in February 1997 was then progressed by CID.

"Brian Field has been interviewed about the missing boys as previously reported, he has not been charged as there has not been sufficient evidence to date to present to CPS to consider such a charge.

"This case remains an open investigation subject to regular review by the force review team, and new evidence or developments will be thoroughly investigated. At the current time and despite the best efforts of the investigation team there is insufficient evidence to pursue a charge, should sufficient evidence become available this matter will be discussed with CPS.

"In respect of Mark Billington, his death in 1984 was treated as a suicide and the coroner returned an open verdict, following this in May 1998 all the information was reviewed and it was subsequently dealt with as a murder investigation.

"This remains an open investigation and it would be inappropriate to comment on individual suspects."

  • The programme is still available to watch on catch-up on Channel Four's website.