Two men will face extended prison sentences after posting crude explosive devices and racist letters to Solicitors in West Yorkshire and Lancashire.
The prisoners from HMP Full Sutton were charged following an investigation by the North East Counter Terrorism Unit last year. Officers from the CTU were alerted by Prison Officers, after they intercepted a letter containing an incendiary device.
A jury at Leeds Crown Court found 23 year old Bret Atkins guilty of Conspiracy to Send an Explosive Substance with Intent.
26 year old Jamie Snow had previously pleaded guilty to Sending an Explosive Substance with Intent and two offences of Threats to Kill.
The pair will be sentenced on September 4, at Leeds Crown Court.
Detective Chief Superintendent Ian Wilson is Head of the North East Counter Terrorism Unit. He said: “Bret Atkins and Jamie Snow waged a campaign of hate against innocent people, choosing victims purely on the grounds of their race or religion.
"They expressed deeply racist and anti-Muslim views and sent a series of threatening letters, designed to instil fear in their recipients.
“Snow and Atkins took their hatred beyond threats to kill and even tried to post explosive materials in an attempt to cause harm or injury.
"Thankfully this mail was intercepted by vigilant officers within the Prison Service and was never able to enter the postal system.
“Snow and Atkins may already be in prison, but they will still be held accountable. We will continue to work with the Prison Service to respond to racially aggravated incidents and punish those who seek to threaten the safety and confidence of our communities.”
Marcella Goligher, Governor of Full Sutton, said: “We are committed to the prevention of crime and are proud of the work our vigilant and highly-skilled members of staff do to detect it.
“These convictions have been secured as a result of strong partnerships, and we will continue to work with the police and the CPS to ensure prisoners who break the law are prosecuted.”
Three prisoners will be charged with allegedly taking a guard hostage after an investigation by counter-terror police.
Feroz Khan, Fuad Awale and David Watson, who were all inmates at HMP Full Sutton in North Yorkshire, are accused of false imprisonment on May 26
Khan and Awale are also accused of threatening to kill the officer, and Khan will be charged with grievous bodily harm on the guard, and assault occasioning actual bodily harm on a second officer.
Following an investigation by the police's north east counter terrorism unit, the CPS has authorised charges against three men currently detained in prison.
"It is alleged that on May 26 2013 Feroz Khan, Fuad Awale and David Watson, all of whom were at that time prisoners at HMP Full Sutton, unlawfully imprisoned a prison officer and detained him against his will. They will be jointly charged with one count of false imprisonment.
"A number of demands were made during the incident which resulted in the case being handled by counter-terrorism officers and specialist prosecutors."
There is a warning today that a top security Yorkshire jail housing terrorists, murderers and rapists could face a potential loss of control because of continued budget cuts.
The independent Monitoring Board for Full Sutton Prison, near York, which holds 600 inmates, has warned the scale of the funding cuts could lead to increased tensions within the jail. It says the prison is well managed, but has found tensions already between Muslims and other prisoners.
The Prison Service says systems are in place to deal with violent incidents quickly and robustly and it says the report will be considered by Ministers who will respond in due course.
Police are investigating after a prisoner was stabbed by another inmate at Full Sutton Prison in East Yorkshire.
A Full Sutton prisoner was stabbed by another prisoner at 4pm on 21.1.13. The prisoner was taken by ambulance to outside hospital and treated for a stomach wound; he was returned to the prison later that night.
The police are investigating and the prison will conduct an internal investigation."