Manchester Arena plotter Hashem Abedi has been charged with three counts of attempted murder after four prison officers were injured at a maximum security prison.
Abedi, 28, is also charged with one count of assault occasioning actual bodily harm and one count of unauthorised possession of a knife or offensive weapon after the incident at HMP Frankland in Durham on April 12.
Counter Terrorism Policing North East said it had carried out a "thorough investigation" of the incident with Durham Constabulary and HMP Frankland.
Abedi, who remains in prison, is due to appear at Westminster Magistrates' Court on September 18.
Three prison officers were taken to hospital with serious injuries following the incident.
Speaking in April , the families of five people murdered in the Manchester Arena bombing say they are in “disbelief” Abedi was able to attack prison officers in HMP Frankland.
Abedi, who had been a long-term inmate at HMP Frankland’s separation centre, was jailed for life with a minimum sentence of 55 years for the murders of 22 people after helping his brother carry out the suicide bombing of an Ariana Grande concert in 2017.
He moved to the separation centre after carrying out an attack on prison officers in London’s MMP Belmarsh in 2020.
The families’ letter to Ms Mahmood says: "We are writing in absolute disbelief" that, once again, the "evil Hashem Abedi has been allowed to cause danger to life".
"As the families of Megan Hurley, Eilidh Macleod, Chloe Rutherford, Liam Curry, and Kelly Brewster, our beautiful, beloved children who were so tragically murdered along with 16 others in the Manchester Arena terror attack in May 2017, we find this situation beyond comprehension."
The Ministry of Justice (MoJ) said it will launch a full independent review into how the attack was able to happen.
In response to the letter, it said in a statement that their thoughts remain with the victims of the Manchester Arena bombing and their families.
An MoJ spokesperson added: "The Government will do whatever it takes to keep our hardworking staff safe, and our thoughts remain with the two prison officers still in hospital as they recover.
“We’ve already taken immediate action to suspend access to kitchens in separation and close supervision centres.”
