Drones are being increasingly used to smuggle drugs, mobile phones and other banned items into prisons, it can be revealed.
Figures show that in 2013 none of the unmanned crafts were discovered in or around English prisons.
But in 2014 this rose to two incidents, rocketing to 33 in 2015 - an increase of 1,550% in that period.
Items discovered include just the drones themselves, drugs, mobile phones and chargers, and USB drives. Prisons affected included HMP Manchester and Liverpool.
Mike Rolfe, national chairman elect of the Prison Officers Association (POA), said: “The use of drones to smuggle traditional drugs, NPS (legal highs) and mobiles phones into prisons is of serious concern to the POA.
“The POA have long pushed for increased staffing resource to tackle the security issue that drones present. The additional resource should be used to increase operational staffing within establishments, allowing for the recovery of parcels delivered to prisoners by drones through cell checks and prisoner searches.
“This includes pressing NOMS (National Offender Management Service) for measures to tackle drones such as ground patrols and secure windows on cells.
“The use of illicit mobiles phones allows for increased criminal activity and distress to victims and their families.
“The trafficking of illegal drugs and legal highs hampers rehabilitation breeding violence, bullying and gang culture. All of these issues are on the increase with the use of drones supporting this criminality.”
Prisons most affected by drone incidents between 2014 and 2015 were HMP Onley in Northamptonshire, topping the list with four, followed by Leicester, Ranby and Swansea on three, and Bedford, Wandsworth and Manchester clocking two each.
Her Majesty’s prisons recording one occurrence include Lindholme, The Mount, Whatton, Leeds, Eastwood Park, Liverpool, Norwich, Glen Parva, Huntercombe, Wormwood Scrubs, Full Sutton, Guys Marsh, Long Lartin, Bullingdon, Wealstun and Oakwood.
The Ministry of Justice said: “Incidents involving drones are rare, but we remain constantly vigilant to all new threats to prison security.
“We have introduced new legislation to further strengthen our powers, making it illegal to land a drone in prison or to use a drone to drop in psychoactive substances.
“Anyone found using drones in an attempt to get contraband into prisons can be punished with a sentence of up to two years.
“We take a zero tolerance approach to illicit material in prisons and work closely with the police and CPS to ensure those caught are prosecuted and face extra time behind bars.”
A report published in December by the HM Inspectorate of Prisons noted that illegal drugs, NPS and illicit medications may get into prisons in a number of ways - meaning it is not always possible to quantify exactly how many drugs are making it into prisons.
With supply routes differing from prison to prison, drugs have been discovered being thrown over fences in tennis balls, in large packages fired by catapults and being dropped by drones.
The report states that “easy access to illicit mobile telephones makes it possible to plan the drops carefully”.
Figures revealed by the FoI show that across the incidents at English prisons, drugs were discovered on at least six occasions, mobile phones more than nine times and a drone itself recovered in 19 instances.
One of the biggest finds listed a drone, drugs, mobile phone, a charger and USB cards being discovered in December last year at HMP Oakwood.