Two Muslim inmates were reportedly behind an attack on five prison officers at Whitemoor high security prison in Cambridgeshire.
The prisoners, who were wearing fake suicide vests, slashed one of the officers in the face and neck when he unlocked their cell at around 9.10am on Thursday, 9 January.
The BBC and Sky News claimed one of those involved in the incident was Brusthom Ziamani, 24, who was convicted in 2015 of preparing an act of terrorism.
— London Crime LDN & U.K Crime (@CrimeLdn) January 10, 2020
The trial heard he had planned to behead a British soldier and admired the pair who were convicted of killing and decapitating Fusilier Lee Rigby in 2013.
The Metropolitan Police has taken over the investigation from Cambridgeshire Police and say they are treating it as a "terrorist attack."
Deputy Assistant Commissioner Dean Haydon, the Senior National Coordinator for Counter Terrorism Policing, has confirmed the incident is being treated as a “terrorist attack”.
Scotland Yard said: “There is nothing to suggest any continuing threat inside or outside of the prison system linked to yesterday's incident. Both the prisoners suspected to have been involved in the attack remain in prison. No arrests have been made at this time.”
— National Chair POA (@POAnatchair) January 9, 2020
The BBC claimed the second inmate was serving jail time for an unspecified violent offence and had converted to Islam in prison.
The jury at Ziamani’s trial heard he had used the internet to research army cadet bases.
Ziamani was 18 when he was arrested by police in 2014 in a joint operation by Scotland Yard and MI5.
He was jailed for 22 years but his sentence was reduced slightly on appeal.
— Connor A. Gurney (@connordoner) January 10, 2020
Whitemoor, which is located in the flatlands of the Cambridgeshire countryside just outside the town of March, houses more than 400 Category A and B prisoners.
Many of the Category A prisoners are convicted murderers and terrorists who are serving long sentences.