Security guard Travis Baumgartner is being returned to Edmonton to face three charges of first-degree murder and one charge of attempted murder in the shooting of four of his colleagues.
Edmonton police have a news conference scheduled for Sunday afternoon.
Baumgartner's arrest at the Lynden, Wash., border crossing southwest of Abbotsford, B.C., brought to an end a 36-hour manhunt.
The 21 year old suspect was handed over to Canadian authorities late Saturday night.
An RCMP officer walked with shackles in hand from the Canadian side of the border to the U.S. side.
Baumgartner, dressed in blue jeans and a long-sleeved white t-shirt, had a look of indifference on his face just before he was placed in the custody of Canadian authorities.
Earlier, the blue four door pickup truck he was believed to have been driving was loaded onto a flatbed truck for transport back to Edmonton.
Mike Milne with U.S. Customs and Border Protection said it was a computerized licence-plate reader that lead to Baumgartner's capture. The plate on Baumgartner's truck had been swapped out with one from his mother's car, but authorities were already wise to that.
As he attempted to cross into the U.S., the reader spit out a warning that Baumgartner was possibly armed and dangerous. Witnesses saw border staff approach with their guns dawn, but Baumgartner surrendered without a fight.
Milne said border officials found $334,000 in Baumgartner's truck, the same one in which police believe he left Edmonton. It was stuffed in a backpack.
Police had been looking for Baumgartner since early Friday when four guards with G4S Cash Solutions Canada were gunned down, three of them fatally.
Police have said Baumgartner was the fifth member of the armoured car crew that was re-loading bank machines at a University of Alberta mall and residence building where the shooting happened.
An armoured car was found after the shooting halfway across the city, not far from the G4S depot. It was running and had its lights on when discovered by police.
Eddie Rejano, Michelle Shegelski and Brian Ilesic have been identified as the guards who died. Matthew Schuman was still listed in critical condition Saturday.
Baumgartner lives with his mother, Sandy Baumgartner, in Sherwood Park, a bedroom community just east of Edmonton. She had released a statement during the manhunt pleading for her son to turn himself in.
Details that have emerged about Baumgartner's life are contrasting.
Friends say he had designs on being a police officer, but settled into a job with G4S a few months ago after deciding he didn't have what it takes for law enforcement.
In an online dating profile, he describes himself as a "great guy" who is laid back and has a "10" physique.
But his Facebook page is much darker, quoting the anarchist Joker from the movie "Dark Knight" and musing about "popping people off."
Rejano, 39, also aspired to be a police officer and was a competitive target shooter who worked a second job as a gun range officer at the Wild West Shooting Centre at West Edmonton Mall.
Shegelski was 26 and had recently married. Her husband, coincidentally, is a student at the University of Alberta.
Brian Ilesic was 35 and had a 12-year-old daughter.
Working at G4S is Schuman's second job. He is also a corporal in the military and works as an Air Force firefighter at the base in Edmonton.
Staff at the university reopened the HUB building Saturday where the shooting happened.
A bouquet of flowers was placed next to the bank machine
Also on HuffPost