Army bomb disposal experts had to be sent to carry out controlled explosions to tennis balls hidden around HMP Wealstun, at Thorp Arch, near Wetherby, during the alert. Ryan Cook, 26, was jailed for three year, nine months, after Leeds Crown Court heard how he made a scripted call from his cell on behalf of others in exchange for being supplied with a legal high. Governors ordered a lock down after Cook made the emergency call on the morning of February 23 last year. Cook told the operator that explosive devices had been placed around the prison. He then said he would call back at 1pm that afternoon before adding: “If you do not release prisoners there will be serious consequences.” Prison officers then discovered suspicious packages within the prison which later turned out to be tennis ball filled with coins and wrapped in duct tape. The incident was treated as similar to a terrorist threat. Members of the Royal Logistical Corps had to be deployed from Catterick Garrison. One officer, wearing a bomb suit, carried out controlled explosions which caused damage to part of the prison building. Major disruption was also caused for the emergency services, with around 30 ambulance staff being sent to the scene. Fire crew were sent and detectives from West Yorkshire Police’s Homicide and Major Enquiry Team took charge of the situation. Police negotiators and teams from the national dog and tactical support groups were sent to the scene. Helicopters were also deployed. Cook, of Oswald Road, Manchester, was arrested when a prison officer recognised his voice from a recording of ten-second hoax call. A mobile phone SIM card was discovered in his cell. Cook, who has served prison sentences for robbery and harassment, pleaded guilty to conveying false information with intent and unauthorised possession of telecommunications article within a prison. Marsha Myers, mitigating, said Cook had made the call after becoming addicted to a legal high known as “spice”, which is readily available within prison. She said: “It is a mind altering, psychologically debilitating drug. That is what he was taking at the time of the offence. “The basis of the call was to cause disruption by those who were his spice suppliers who had ulterior motives. “The desperate Ryan Cook stupidly became involved because his primary concern was to get his fix.” Judge Tom Bayliss, QC, said: “You caused danger to those still within the prison and you caused panic within the close confines of the prison. “You must have known that was a likely outcome of what you were doing. “A huge number of emergency services personnel had to be alerted and deployed.” Detective Superintendent Nick Wallen, of West Yorkshire Police Homicide and Major Enquiry Team, said: “Cook’s hoax call sparked a major incident involving a large-scale emergency services response including an army bomb disposal team, police, fire and ambulance staff, specialist detectives and police negotiators. “It led to the prison being locked down, an evacuation of part of the site and a controlled explosion being conducted on the suspicious packages that were found. “This caused significant disruption to the normal operation of the prison and tied up a number of emergency services resources that should have been available to deal with genuine incidents. “We believe Cook was acting as part of a plan to use the disruption to get drugs smuggled into the prison and that his reward was to be a share of those drugs. “Instead he now finds himself spending even more of his life behind bars. “This case clearly highlights the risks presented by the illegal use of mobile phones by prisoners and we will continue to work closely with the prison authorities to tackle the issue.”