An investigation into one of Canada's worst mass killings in a remote Indigenous community last year has found evidence suggesting the suspect planned it in advance with his brother, according to police.
The stabbings in September 2022 left 11 people dead and 18 injured before the suspect, Myles Sanderson, was arrested.
He and his brother Damien had been seen "guzzling booze" and "pumping themselves up" in the hours before the attacks, Royal Canadian Mounted Police Superintendent Joshua Graham told a news conference.
"The investigation has determined this is the beginning of the mass casualty homicides," he said, outlining a chronology of the killings in the James Smith Cree Nation and nearby village of Weldon in Canada's western Saskatchewan province.
Damien Sanderson had also spoken to a female acquaintance at a local bar, saying he and his brother had "a mission to do" and that "people would hear all about it in the next few hours," according to Supt Graham.
The killings led to a major four-day manhunt that culminated in Myles's death in custody after he was stopped on a roadside following a police chase.
Damien, who had initially been identified as a suspect in the murders, was found dead.
Supt Graham said the siblings had had a falling out at the onset of the attacks and Myles killed Damien.
The investigation involved 42 crime scenes, including several homes that Myles forced his way into, and more than 200 witness interviews.
Police said the brothers assaulted several people - which went unreported at the time - drank a lot and sold drugs in the community in the hours leading up to the killings.
Myles later went house to house looking for his victims in stolen vehicles and on foot.
In addition to Damien, six men and four women - aged between 23 and 78 - were killed.
All but one were members of the Cree community.
The other was a widower who lived with his adult grandson in nearby Weldon.
Seventeen adults and one young teenager were wounded in the attacks, police said.
