Three inmates have been cleared of stabbing a new father to death in a war over phones and drugs smuggled into the crisis-hit Pentonville prison.
Jamal Mahmoud, 21, was killed in October last year as the 175-year-old jail struggled with overcrowding, staffing, and violent factions fighting to control the lucrative trade in contraband.
During an Old Bailey trial, jurors were told CCTV which might have captured the killing on the upper floor of G Wing had been deactivated years ago.
On a tour of the heavily-criticised north London jail, the jury saw a gaping hole in netting above the building designed to stem the flow of contraband by drone.
The jury deliberated for more than one-and-a-half weeks to find Basana Kimbembi, 35, Robert Butler, 31, and Joshua Ratner, 27, not guilty of murder.
However, the 11 men and women convicted Kimbembi of wounding Mr Mahmoud's friend Mohammed Ali with intent to cause grievous bodily harm.
The defendants nodded and Butler said "thank you" to the jurors following the verdicts.
Judge Richard Marks QC adjourned Kimbembi's sentencing until Monday.