“Following the arrest and subsequent charging of a prison officer who allegedly attempted to bring contraband into Christchurch Men’s Prison in March, further investigations have revealed potential illegal activities by gang members working in an engineering workshop on the premises,” she said.

“It involved prisoners producing items, probably motorcycle accessories, and organising their transport outside the facility.

“Any staff member identified as potentially involved in illegal activity will be subject to further investigation and may face charges by the police.”

Marsh said two prisoners had their employment contracts at the workshop terminated and their security clauses were being reviewed.

“This type of behavior is not tolerated and we take any allegations of this type extremely seriously.”

Mr March said prisoners often went to extreme measures to continue their crimes in prison, with some putting significant pressure on people to continue their illegal activities in prison.

Police said they were aware of the matter but could not comment further at this stage.

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