Fresh assault charges against Renata

Cole Miller's killer has had his sentencing put off amid allegations he assaulted prison guards earlier this year.

New Zealand national Armstrong Renata was due to be sentenced in the Brisbane Supreme Court on Monday having previously pleaded guilty to a count of unlawful striking causing death.

The 23-year-old punched Mr Miller in the back of the head while out in the Fortitude Valley nightclub district on January 2, 2016.

The 18-year-old suffered massive brain trauma, with his family making the heartbreaking decision to turn off his life support the following day.

Renata was escorted into the dock in handcuffs on Monday flanked by an unusually large number of security guards.

The court heard he had been charged with two counts of serious assault and his legal team needed time to assess the new allegations.

Renata and another prisoner are alleged to have assaulted three custodial officers at the Woodford Correctional Centre on April 11.

The officers were taken to hospital for assessment.

Renata's sentencing was adjourned to July 21 for review, while the new charges will be heard in Caboolture Magistrates Court on July 19.

Outside court, lawyer Adam Magill said Renata was "all right" but he had been asked by the family not to comment.