In what witnesses are describing as a horrific scene, former All Black Joe Karam has been found dead along with a number of other prominent Bain supporters, including lawyer Michael Reed and retired Canadian judge Ian Binnie, in the Christchurch home of David Bain.

Police say there were five victims in total, but have yet to name the remaining two.

The deceased were reportedly meeting with Bain to discuss plans for the ongoing compensation claim concerning his now-overturned conviction of killing his family in 1994. Bain had allowed the five supporters to stay the night, and they were discovered dead early this morning, each in different rooms and with fresh bullet wounds.

Police say that the lone survivor of the killings, David Bain, was horrified to discover the men's bodies after returning home from his morning paper round.

Bain says he entered the home at around 8:20am, before absent-mindedly walking past several of the deceased on his way to the laundry. Here he discovered a pile of bloodied clothes, which he carefully washed before returning to his living room to fully realise that all his friends were dead.

Bain then made a frantic 111 call, telling the operator "Help. They're all dead. My friends, they're all dead. Hurry up."

After conducting a full survey of the scene, police discovered Karam's body in the living room next to a large hunting rifle, as well as a message left on Bain's home computer that read "Sorry you are the only one who deserved to stay."

Police Detective Inspector Dave Long said that while the investigation was still thoroughly underway, the person responsible for the killings should be "plainly obvious."

"We're not willing to draw absolute conclusions at this stage, but it does appear likely to us that Karam, for some reason, has turned on his fellow Bain supporters," he said. "He's taken Bain's hunting rifle, he's shot the rest of them, and then he's gone and changed out of his bloodied murder clothes and put them in the wash.

"He's then walked into the living room, probably spent a good half-hour to an hour trying to get that rifle against his head, pulled the trigger, he's dead. Now Bain comes home, sees a few dead bodies, makes his way to the laundry to do the washing like he always does. Finds a bloody pile of clothes, washes them, because, well, they're filthy.

"He then makes his way into the living room, sits down, turns on the TV, and a little while later, suddenly notices that everyone is dead."

Long said it made sense because Karam "loved Bain," and that's probably why he let him live.

Bain was not expected to be charged following the incident.