ST. CATHARINES, Ont. -- An Ontario man accused of killing his seven-year-old stepson and badly injuring a banker with whom he'd once had professional dealings managed to flee 2,000 kilometres over four days before being arrested, police said Wednesday.

Niagara regional police Chief Jeff McGuire said the nationwide manhunt for 43-year-old Justin Kuijer, which began in St. Catharines, Ont., came to a peaceful end in the parking lot of a Walmart in Kenora, Ont., around 5 p.m. on Tuesday.

A member of the public who had heard of the search for Kuijer recognized the van in which the man allegedly fled. Six provincial police officers responded to the tip and arrested the former roofing company owner without incident, McGuire said.

Kuijer had been the subject of a Canada-wide warrant on a charge of second-degree murder in the death of his stepson, Nathan Dumas, but McGuire said the man will in fact be charged with first-degree murder in the boy's death, as well as attempted murder in the attack on the bank employee.

McGuire credited steady media exposure and public vigilance for Kuijer's arrest, saying the end of the manhunt can help a devastated community begin to heal.

"It's because of those efforts that Kuijer is in custody today, and the community is safer than it was before his arrest yesterday," he said at a press conference.

Outside a St. Catharines sandwich shop owned by Nathan's grandparents, flowers and stuffed animals formed a makeshift memorial for the slain boy.

Residents walking by expressed rage at the attacks and relief that a suspect had been caught.

Ken Chipman, who was walking his dog near the school Nathan attended a short drive away, said news of the attacks had left him "really upset."

"I thought it was horrible," he said, adding he was glad the search for Kuijer was over.

McGuire provided few new details on Kuijer's alleged crimes or on the massive manhunt, citing the need to keep certain details confidential. But he did provide insight on how police began their investigation.

Police were first summoned to a RBC branch in St. Catharines on Friday morning after reports of an assault. Officers found an employee suffering from stab wounds, he said.

McGuire confirmed that the woman, who has not been named, had worked with Kuijer on financial matters in the past.

Witnesses reported seeing Kuijer fleeing the scene in a dark grey van, which enabled police to connect the attack at the bank to another call they were fielding at essentially the same time, he said.

Across town, in a home above the family's sandwich shop, police said a relative discovered that Nathan had been critically injured.

The boy was rushed to hospital with undisclosed injuries and died the next morning. Police learned that the van in which Kuijer allegedly fled the bank was registered to the address where Nathan was found.

McGuire said the dual attacks had a wide-ranging impact across St. Catharines, a small city in the heart of Ontario's wine country.

He read a note from a staff member at the school Nathan attended which outlined the grief experienced by staff, parents and fellow students.

Another anecdote from McGuire highlighted the national scope of the hunt for Kuijer.

"One of the detectives answered the phone, and it was two officers sitting on the side of the TransCanada Highway in Alberta to say they that they're out looking for our man," he said.

McGuire said Nathan's mother and the RBC victim were "elated" at news of Kuijer's arrest, but were asking to have their privacy respected in the wake of the attacks. The bank employee remains in hospital but is expected to make a full recovery, he added.

Kuijer will be returned to the Niagara region on Wednesday in advance of a bail hearing scheduled for Thursday.

The next day, Nathan's family plans to lay the boy to rest at a funeral in neighbouring Thorold, Ont.

"Nathan was truly a kind, loving boy with a big heart, full of compassion for everyone and everything. He was always quick to help anyone who may have been in need," reads an obituary for the boy.

"As the polite young gentleman he was, he never missed an opportunity to open a door, give a gift or come to the defence of a good friend. Nathan truly felt the joy of giving, never looking for anything in return. There are no words to express the unbearable heartbreak we feel in his loss."

Nathan is survived by his mother and younger siblings, the obituary states, adding that his little brother looked up to him as a "best buddy" while his baby sister will be told growing up "what an amazing big brother she had"

-- with files from Michelle McQuigge in Toronto.