Edmonton Police said Jayme Pasieka, 29, was expected to be charged with two counts of first-degree murder, one count of attempted murder and weapons offences. Staff Sgt. Bill Clark said more charges could come as the investigation continues.
Pasieka was arrested after a man with a knife in each hand and wearing a military-style vest, burst into the Loblaws warehouse in a northwest industrial area during shift-change and started stabbing people throughout the complex.
Witnesses described a frantic scene as workers feld for their lives.
Clark said the attack lasted just minutes, but it was "complete chaos" when emergency crews arrived.
One person was dead in an aisle. Another died in an ambulance outside. Four others were stabbed. One man was seriously injured and remained in hospital Saturday. Clark said his condition had stabilized.
Pasieka had worked at the facility some time filling orders, but Clark said investigators still don't know the motive for the attack.
"We have some ideas about what may have caused it ... but honestly we just don't know right now," Clark told a news conference on Saturday morning. "It's just too early in the investigation."
Police have identified the dead as Fitzroy Harris, 50, and Thierno Bah, 41.
A friend of Bah's, Thierno Gando Bah, said Thierno Bah was a married father of four young children.
"We are all in shock. We can't believe what happened," Bah said.
Harris's family, meanwhile, emailed a statement to media noting his talent as a DJ and love of reggae music.
Court records show Pasieka had a history of erratic behaviour.
A judge convicted Pasieka of assault with a weapon and uttering threats in 2010 and he was sentenced to 15 months probation.
The judge's decision detailed how Pasieka had thrown eggs at neighbour Devon Sandford's vehicle and set a heart-shaped fire on their street one night in 2009. When Sandford confronted the cloak-wearing Pasieka, court heard Pasieka came at him with a bow and arrow.
The officer who arrested Pasieka that night said he found bear spray, a collapsible baton and a knife in Pasieka's house.
Pasieka told police he did what he did in the name of The Queen. Police said he stood at attention while being searched, saying one day wanted to join either the police or the military.
At trial, Pasieka admitted to the egging was a poor attempt on his part to get to know his neighbours. He said he lit the fire because he was upset over a recent break-up.
Pasieka's father, Samuel, testified that his son suffered a concussion in an accident three years earlier and, since then, had taken longer to understand things.
It took police three hours to track their suspect down after he fled the warehouse Friday. They released his picture and warned the public he was dangerous.
An alert citizen recognized Pasieka sitting in his vehicle in an industrial area on the city's south side. Pasieka was arrested without incident, about a block from the electrical business of which Sandford is listed as owner on Linkedin.
When contacted Saturday, Sandford's father-in-law, Victor Carreiro, who was there that night in 2009, said the family didn't want to talk about the case.
"It's just very upsetting," he said.
Clark said Pasieka was well-known to the people inside the warehouse but it was too early to say if anyone was specifically targeted.
Police wouldn't say what Pasieka has told them since his arrest.
"I can tell you that he has been very calm, very polite and he has been co-operative," Clark said.
Thieno Gando Bah said he and his friend knew each other from their homeland, the West African country of Guinea.
He said Thierno Bah first arrived in Canada in 2009 and had a master's degree in nanotechnology, but had difficulty finding work in his field because his English was weak. Thierno Bah and his family moved to Edmonton in October to improve his fluency, his friend said.
"He's the last person you would think something like this would happen to," he said. "He was a family guy, friendly, always ready to help.
"What's happened is just insane."
He said members of the local Guinean community were planning to raise funds to return the body to Africa.
"The entire Guinean community is in mourning and is coming together to oversee the upcoming memorial," read a post in French on Facebook.
The statement from Harris' family expressed anger at his killer.
"Shame on you coward," it read. "That is not how you deal with your issues. Mental health treatments nor medication will not help you.
"May God not have mercy on your soul."
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