"Significant progress has been made in the investigation to date, with a number of the gang's members and associates giving police invaluable information.
"However, we still believe there is further information being actively suppressed by the gang," Alexander said.
"We know that there are people within the Tribesmen gang who know what happened on that day and police are as determined today as they were seven months ago to resolve this investigation and seek some resolution for Mr Ratima's family and friends."
Anybody with any information is urged to contact Albie Alexander on 09 261 1300, alternatively, they can contact Crimestoppers anonymously on 0800 555 11.