Investigation begins into Elmley Prison 'bullying assault'
An investigation has begun after a video emerged of two young prisoners being punched during a "bullying ritual".
The Sunday Mirror published a video of the male inmates being assaulted at Elmley Prison on the Isle of Sheppey.
Kent Police said they were treating the incident, on 3 May, as grievous bodily harm.
A Prison Service spokesman said "swift and robust" action was taken against perpetrators of violence.
"We do not tolerate violence of any kind," he said.
"This incident has been referred to the police, who are investigating."
Mike Rolfe, from the Prison Officers Association, said the prison housed people who had just come into custody.
"It could be that it's their first time in custody. They are particularly vulnerable when they first come in; they're open to bullying because they don't understand how the prison works," he said.
The category C prison, near Eastchurch, houses sentenced and unsentenced adult men and unsentenced male young offenders.