The fight is believed to have taken place in HMP Featherstone in Staffordshire as inmates crowded round the event.
A gang of around 20 prisoners can be heard egging on the violent offenders as the fighters trade punches with one screaming: “Finish him”.
At least three mobile phones, which are banned in British prisons, were used to film the outrageous five minute duel.
Not one single security guard is seen during the barbaric clip as inmates make gun signals towards the camera.
In the footage, one of the prisoners can be heard saying “keep the door locked” as the boxers prepare for their fight.
One of the fighters batters the other prisoner in front of the crowd
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Next the mobile phone camera pans the crowd with many of the prisoners laughing and joking waiting for the bout.
Some of the convicts however are wary of the guards outside who may be able to hear them before one of them says: “Shhh, yo be quiet, man”.
Other inmates are even heard saying: “Keep the door locked, man” and “gang members only.”
Next the battle begins with both prisoners laying thunderous strikes on each other before one is eventually beaten to the floor.
The footage was uploaded to Facebook on February 3 and shows one of the fighters walking up to the camera grinning as he poses with both thumbs up.
A spokesperson from the Ministry of Justice said: “We will not hesitate to take disciplinary action against those involved.
“This behaviour is completely unacceptable and we are working to remove the content from social media.
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One inmate was bashed to the floor during the bloody fight
This behaviour is completely unacceptable and we are working to remove the content from social media
Ministry of Justice spokesperson
“We have reported this incident to the police and are stepping up measures to find and block mobile phones in prisons and those found with them can face extra time behind bars.
“We are committed to making prisons places of safety and reform and are stepping up measures to tackle violence and find and block mobile phones in prisons.”
HMP Featherstone is a Category C men's prison which houses more than 600 inmates.
In August last year, a major incident was declared at the jail after inmates set fires and assaulted guards in a week-long outbreak of disorder.
Around 3,000 mobile phones were seized in just 12 weeks in UK jails last year. They are smuggled in by visitors, corrupt guards and even dropped over prison walls by drones.
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