Inmates at Pentonville Prison shouted and complained they were “locked up like animals” as a judge and jury went behind bars to view the site where a 21-year-old new father was stabbed to death.

Islington Gazette: Jamal Mahmoud was stabbed to death inside Pentonville Prison. Picture: Metropolitan Police/PA WireJamal Mahmoud was stabbed to death inside Pentonville Prison. Picture: Metropolitan Police/PA Wire

Judge Richard Marks and a team of prosecution and defence lawyers dispensed with wigs and gowns when they escorted the 12-strong jury on a tour of the Caledonian Road jail.

The trial has heard how Jamal Mahmoud was allegedly killed by three fellow inmates in a battle to control the trade in phones and weapons being smuggled into the prison by drone or other methods.

The location of Mr Mahmoud’s cell on the fifth floor of G Wing occupied a prime position, giving him power over the influx of contraband, jurors have heard. The day before the killing a package had come into the prison and there was open talk of a “beef”, the trial has been told.

Three defendants allegedly armed themselves and attacked Mr Mahmoud in an area of G Wing not covered by CCTV, jurors have heard.

Robert Butler, 31, Basana Kimbembi, 35, and Joshua Ratner, 27, have denied murdering Mr Mahmoud on October 18 last year. The men waived their right to join the site visit to Pentonville.

Jurors, judge and lawyers alike were subjected to bag and body searches with sniffer dogs before being allowed into the jail yesterday.

Once inside, the group was shown past coils of barbed wire and peeling paintwork and through heavy metal doors into the central atrium linking the wings of the prison which houses more than 1,000 men.

Prosecutor Mark Heywood QC pointed out new features added since the murder, including metal detector archways, extra metal grilles and new windows on cells.

He also showed jurors the location of netting and CCTV cameras on the wing which were in place at the time.

Inmates were on lockdown in their cells and could be heard listening to music and making noise.

One inmate on the third floor banged loudly on his door and shouted “not guilty, not guilty” before being told by a prison officer to “pipe down”.

As the group progressed through the floors there was more shouting of “I want justice for my friend. My friend was killed”.

Another inmate exclaimed loudly behind his door “it’s a horrible place”, as jurors walked by to view a cell containing a bunk bed, toilet, wash basin and graffiti scratched on the wall.

Outside in the exercise yard, as Mr Heywood pointed out overhead netting and the position of cells, he was partially drowned out by prisoners shouting out of their windows on two sides.

Comments included “f*** the law”, “locked up like animals”, and “scumbags here, mate”.

Back inside the wing, jurors were shown the locker and shower room.

The men and women held their noses at the smell with one commenting “it’s disgusting” as she emerged.

At the end of the two-hour tour of the cockroach-infested facility, one of the jurors joked they were going to “stay here all night” as they queued up to leave.

The trial continues.

Reporting by Press Association