Six officers are said to have been hurt after bosses lost control of the C wing at HMP Whitemoor in March, near Cambridgeshire.
A “tornado team” elite enforcement squad was scrambled after the lags lashed out, with one guard said to have suffered a split nose.
Another was reportedly hit by a “flying pool ball” during the violence which raged for two hours.
Six officers were rushed to hospital after the incident at the prison, which has been described as a “major incident”, Cambs Times reports.
“One got hit straight in the eye”
“One got hit straight in the eye” during the disorder, a prison source told the newspaper.
Others were left with “bad bruises and numerous injuries”.
The incident has led to fresh calls for all officers to be armed with Pava – a synthetic pepper spray – which is currently being trialled in a handful of prisons.
The Government insist it should only be used in “exceptional circumstances” as The Prison Reform Trust warned it could cause more harm to fragile prison officer and inmate relationships.
The Category A prison is home to more than 400 of Britain’s most dangerous men, including dozens of convicted terrorists.
Inmates include Nezar Hindawi, doing a 45-year stretch for trying to blow up an El Al airliner at Heathrow in 1986.
Zia Ul Haq, who tried to bomb the London Underground, was sent to Whitemoor after being jailed for 18 years in 2007.
The prison was put on lockdown after a DIY bomb blast on Boxing Day 2015 – amid fears of an escape attempt.