The Prison Service has begun to use technology to detect illicit mobile phone calls in prisons.
The Ministry of Justice (MoJ) said the equipment has been introduced in five prisons so far and can be used to uncover activities such as drug smuggling plots.
It can send real time alerts when a phone is used behind bars, using a digital map in identifying the strength of the signal and the location to the precise cell.
Prison wardens can also track data over time to watch for emerging patterns, such as the timing of drug deals and planned violence.
For security reasons, only basic details about the technology have been released and the five prisons have not been identified.
One step ahead
Justice Secretary David Gauke said: “As criminals look for new ways to smuggle contraband into prisons, it is vital that we stay one step ahead, and this kind of technology will help prevent them operating from their cells.
“This is vital to ensuring prisons are places of safety and rehabilitation, where offenders can turn their backs on crime for good.”
Authorities have identified the illegal use of phones as one of the most significant threats facing the prison service.
In the 12 months to March last year, there were 10,643 incidents where mobiles were found in prisons in England and Wales, a 15% increase compared with the previous year.
Earlier this month, it was revealed that the number of social media accounts shut down at the request of prison authorities had surged after hundreds of inmates used smuggled phones to post from behind bars. And last month, three dead rats stuffed with mobiles and drugs were found at HMP Guys Marsh in Dorset.
The MoJ said the phone detecting technology is part of a wider multi-million-pound strategy to restore stability to prisons.
Other measures include security scanners, improved searching techniques, phone blocking technology and a financial crime unit to target criminal kingpins operating in jails.
The Interference with Wireless Telegraphy Act, passed last December, gave prisons the power to disrupt mobile telephone signals and prevent illegal use of mobiles by inmates.
Image from GOV.UK, Open Government Licence v3.0