Police and prison officers braved mind-numbing temperatures to prevent drugs and other illegal contraband being smuggled into Armley Jail.
Mounted police and sniffer dogs were used in a special operation yesterday in a bid to stop people passing illegal drugs such as heroin and cocaine, mobile telephone components and potential weapons to inmates.
Outside suspect cars flagged up by police intelligence and automatic number plate recognition cameras were stopped and searched by officers from the West Yorkshire Police Operational Support Unit supported by the North West Leeds Neighbourhood Policing Team.
On the trail of drugs being smuggled on the person of visitors were two of HM Prison Service's youngest recruits – three-year-old Millie and one-year-old Lola, two of the cutest, but most determined sniffer dogs.
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Checking passers-by near the prison and on the lookout for anyone suspected of planning to throw forbidden items such as drugs over the wall to waiting inmates, were a team of officers from the West Yorkshire Police Mounted Section and their four trusty steeds.
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Inside the prison authorised visitors were searched as part of the normal routine security screening.
Insp John Hampshire said the operation was not in response to any upsurge of smuggling into the prison but was part of the continuing partnership with the Prison Service to maintain security.
Apart from drugs and mobile phones, officers would also be looking for phone parts such as SIM cards and batteries and recording equipment which were forbidden to inmates and posed a potential security risk.
He said there was no desire to be oppressive to visitors and only people or vehicles who had been brought to the attention of the police through various sources of information were likely to be checked.
Force Drugs Co-odinator, Bryan Dent said: "It is in everyone's interest that people who are in prison are released drug free, otherwise upon release they very quickly reoffend to pay for their drug habit.
"I would warn anyone thinking about smuggling drugs into prison they will be caught and face serious consequences."
Leeds Prison Governor Paul Baker said: "When drugs get into prisons, it undermines all the good work taking place to rehabilitate offenders.
"Drugs cause violence and intimidation inside prison and obviously make it much harder for offenders to become and remain drug free.
"We believe that stopping drugs entering prisons is an integral strand to cutting crime, reducing re-offending and making West Yorkshire communities safer place."