Tim Bosma's remains — "burned beyond recognition" — were found in Waterloo Region, which is about 50 kilometres away from his home, police said Tuesday.
A Toronto man is under arrest and will be charged Wednesday with first-degree murder, Hamilton Police Det. Sgt. Matt Kavanagh said. Investigators are looking for at least two other suspects.
Dellen Millard, 27, was arrested Friday and is already charged with forcible confinement and theft over $5,000. His lawyer has previously said he will dispute the charges.
Police were searching two properties Tuesday in the Waterloo area that are owned by Millard, including an airport hangar and a farm. Officers combed the grounds of the farm on foot and on horseback and at least one cruiser remained parked outside the wire fence.
Bosma, described as a church-going family man not previously known to police, vanished the night of May 6 after leaving his Hamilton home in his black 2007 Dodge Ram pickup truck with two men. The second man police are seeking is described as a white man in his early to mid 20s, about 5-9 or 5-10 with a small to medium build and dark hair, wearing a red hooded sweatshirt.
Police are also looking for at least one more person, as video evidence shows another vehicle following Bosma's pickup truck when he left on the test drive, Kavanagh said. Police haven't been able to make out the vehicle's model from the footage, only that it is an "SUV-type vehicle," and don't know how many people were in there.
"From the evidence that we have right now, I believe that Mr. Bosma died that night," Kavanagh said. But as for a motive, Kavanagh said he doesn't yet know.
There was "no connection whatsoever" between Bosma and the suspects before May 6, Kavanagh said.
A Toronto man earlier took the same two suspects for a test drive of his own Dodge Ram truck, also put up for sale online, police have said. There is no suggestion they were looking for Bosma there, Kavanagh said.
Bosma's cellphone was found three days later in an industrial area of the neighbouring city of Brantford.
However, "no other vehicle" can be seen on surveillance video in that area, Kavanagh said. The cellphone led investigators to Millard, he added.
Police found Bosma's truck Sunday parked in the driveway of Millard's mother's home in Kleinburg, Ont., north of Toronto. She has "absolutely no" involvement with the case, police said.
Search warrants are being executed on a total of three different vehicles, Kavanagh said. Auto squad investigators will also be called in to the airport hangar to examine vehicles in there, he said.
Police don't yet know where Bosma was killed or when his body was burned, only that his remains were found in the Waterloo Region. The coroner's office has just been brought into the investigation and has not yet established a cause of death.
The first-degree murder charge is based on the forcible confinement allegations, Kavanagh said. The charge, often used in planned and premeditated murders, is also used when someone is killed while they are being forcibly confined.
"He entered that vehicle of his own free will, but he was not allowed to leave, therefore forcible confinement is the proper charge," Kavanagh said when asked about the charge.
Scores of police officers are still following up on a multitude of tips, Kavanagh said. Bosma's disappearance captured a lot of public attention, with many expressing concerns for his safety on social media.
A Facebook page in his honour was flooded with condolences Tuesday as the sombre news spread.
"The agony in this house is indescribable. There will be no further updates from this page. My prayers are with this wonderful family," wrote Peter Lowe, a Bosma family friend who has been acting as their spokesman.
The Millard family has a storied aviation history in the region. When Millard was 14 he became the youngest Canadian to fly solo in both an airplane and a helicopter. His grandfather, Carl Millard, was at the time the oldest commercial pilot at 85 years old.
Wayne Millard, Dellen's father, was also a pilot and died in December. Dellen Millard wrote his father's obituary.
"His hope was for a time when co-operation would be the norm and competition was only friendly," Millard wrote of his father.
"He would answer a question with a story. He stepped carefully while advocating carefreeness. He could read and write five languages. He was patient and stubborn. He admired Christ, Gandhi and Lindbergh."
Wayne Millard defined himself by the responsibilities of being a pilot, wrote his son, who added that he now carries his father's pilot's licence in his wallet.
"Piloting wasn't just his job, it was his freedom," Dellen Millard wrote. "He believed we can make a difference in the world. With Wayne in my heart, I believe we must."
Police have asked that Bosma's family be allowed to grieve in privacy. Both his wife and his mother had issued emotional pleas for his safe return.
Ontario NDP Leader Andrea Horwath, who is from Hamilton, offered condolences to the Bosma family.
"I'd like to take an opportunity on behalf of Ontarians and members of the legislature to let the family of Tim Bosma know that we are grieving with them," she said following the police chief's announcement.
"His wife Sharlene, his daughter, and his mother Mary and all his friends and family are grieving very much today, and I think it's important that we say we're grieving along with them."
Prime Minister Stephen Harper and Ontario Premier Kathleen Wynne also expressed their condolences to the victim's family on Twitter.