Last night, Canterbury Police said two people had handed themselves in after a plea via social media to identify two people -- a man and a woman -- of interest.
A total of five people involved in the incident have been formally interviewed by police officers.
Despite the new developments, police are still calling for anyone who may have witnessed or recorded the incident to come forward.
Authorities are still reviewing other CCTV security footage from around the immediate area and say they are "keeping an open mind".
**Anyone with info can call Christchurch Central Police: (03) 363 7400 or anonymously via CrimeStoppers: 0800 555 111.