The shooter identified himself as "Brenton Tarrant" - a white, 28-year-old Australia-born man, NZ Herald reported. The livestream began as the gunman drove to the Al Noor Mosque in Deans Ave, parking his car in a nearby driveway.
According to NZ Herald, the beige stationwagon contains a cache of weapons and ammunition in the front passenger seat and boot, along with petrol cannisters.
The gunman was armed with at least one semi-automatic firearm and multiple ammunition clips. Messages in white writing were scrawled on the gun and ammunition.
Once inside he began shooting indiscriminately. A second victim tried to crawl for their life in the main hallway but was shot several more times.
People cowering in corners of a room were all shot as the gunman blocked the hallway, cutting off anyone's attempt to escape.
The gunman stalked the mosque rooms firing repeatedly, stopping several times to re-load, NZ Herald reported.
He then exited the mosque through the front door - after just under three minutes inside and headed into the street - firing random shots as cars drove past.
He returned to a beige Subaru stationwagon parked in a nearby driveway to get more ammunition from the boot.
He fired more shots on the street at no apparent target and said: "Looks like we won't get the bird today boys".
He then re-entered the mosque to check for survivors - and began firing again into the people lying motionless.
The 17-minute video ends as the gunman drives away from the scene at speed.
In a lenghty manifesto published online the supposed shooter outlined who he was and why he carried out the massacre at the Christchurch mosque, NZ Herald reported.