Three Christchurch prisoners charged with murdering another, have all pleaded not guilty.

Levi Reuben, Akuhatua Tihi and Steven Betham appeared by video link at the High Court in Christchurch this morning.

The trio, aged 21, 22, and 36, allegedly assaulted Benton Parata in Christchurch Men’s Prison last month.

The 44-year-old died in hospital six days later.

The three accused next appear for a case review hearing on June 26.