BORALLON Correctional Centre is in lockdown as an inmate armed with a pair of scissors stages a rooftop protest.
Alex Richmond-Sinclair, 25, has been on the roof since 11.30am Monday.
A Department of Corrective Services spokesman said police negotiators were called in and had been talking to Richmond-Sinclair ever since.
It is believed he is protesting about not receiving proper medical attention for a sore shoulder.
He has been isolated from other inmates and security has not been compromised.
Police are guarding the prison entrance and delivery vans, mail vans and visitors have been turned away.
Richmond-Sinclair is serving a 12-year sentence for bashing another prisoner to death at Woodford Correctional Centre in July 2006.
He was sentenced in August 2008 and has a parole eligibility date of May 8, 2016 and a full-time release date of October 9, 2018.
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