A high-security prison west of Brisbane remains in lockdown this morning after six prisoners gained access to the roof.

Borallon Training and Correctional Centre at Ironbark was placed into lockdown around noon on Sunday as part of the “code silver” incident.

A Queensland Corrective Services spokesperson confirmed four prisoners descended from the rooftop overnight without injury but two remain.

The centre will remain in lockdown to ensure the safety of officers and prisoners until the matter is resolved.

The four prisoners will be held in the Detention Unit, pending investigation by the Queensland Police Service’s Corrective Services Investigation Unit.

They will be brought before the courts if the investigation finds any criminal action occurred during the incident.

They will also be subject to internal prison discipline processes.

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