The Ontario Provincial Police are investigating after the remains of a missing man were discovered on a residential property in rural southeastern Ontario, months after the remains of two other men were found there.

Police announced Tuesday that remains discovered on a property on Kelly Jordan Road in Montague, a tiny township roughly 75 kilometres southwest of Ottawa, belong to Lawrence Bertrim, who was reported missing almost four years ago.

Mr. Bertrim was 42 when he was last seen in September, 2022, in downtown Smiths Falls, just a few kilometres away.

The OPP said in a news release Tuesday that Mr. Bertrim’s cause of death has not yet been determined, as Detective Inspector Jennifer Patton stressed that their investigation “is far from complete.”

The release said it was the third set of human remains to be found on the property.

Investigators found the first set of remains on the property last fall, while executing a search warrant there on Oct. 30, the release said. Those remains were later confirmed to be those of Robbie Thomson, a Smiths Falls man whose family had reported him missing two years earlier, when he was 34, police said.

Three people – Christopher Fenton, Erin Mackie and Joshua Belfiori – have been charged with the first-degree murder of Mr. Thomson. A fourth person, Mark Fenton, is charged with being an accessory after the fact.

Last month, police discovered a second set of remains on the property, which a postmortem examination identified as Robert Lambert, according to the OPP release. Mr. Lambert had been reported missing in November, 2018.

Police previously said Mr. Lambert moved to Ontario from the United States around 2004 to marry his fiancée, Kathy.

“They had a good life in the Smiths Falls area, until Kathy passed away in 2016,” OPP Detective Inspector Serge Acay said in a video posted to social media by the service on Aug. 1, 2025. “Robert was then alone, with no biological family. He was last seen in the summer of 2018, but was not reported missing until that fall.”

Mr. Lambert was 75 at the time, Det. Insp. Acay said, and relied on care from personal support workers. He needed help to travel and required regular medication.

After Mr. Lambert was reported missing, Det. Insp. Acay said, police were initially told that he had gone back to the U.S. – but there was no record of him leaving the country.

“We are confident someone has a crucial piece of information that will help the OPP determine what happened to Robert Lambert,” he said in the video, announcing a $50,000 reward for any information leading to an arrest and conviction in the case. A similar reward was also established for information in Mr. Beltrim’s case.

Property records show Mr. Lambert purchased 572 Kelly Jordan Rd. in Montague Township in 2004.

Christopher Fenton was added as a co-owner of that 40-acre property in April, 2018 – months before Mr. Lambert disappeared. Mr. Fenton was also named Mr. Lambert’s power of attorney, according to property records.

Mr. Fenton’s lawyer did not immediately respond to a request for comment.

Lawyer Jenny McKnight, who is representing Ms. Mackie, said in an e-mail that her client is “shocked and is trying to process this summer’s new information.”

A lawyer for Mr. Belfiori declined to comment.

As with Mr. Bertrim, police said the cause of Mr. Lambert’s death has not yet been determined.

On Tuesday evening, the heavily wooded property remained taped off and guarded by police.

In an e-mail statement Tuesday, Karen Jennings, the reeve for Montague Township, described this latest discovery as “heartbreaking news for our community.”

“The municipality recognizes that news of another found body can be deeply distressing for residents and for those who are connected to the individuals and their families, but we continue to be advised by the OPP that there is no threat to the public at this time,” she said. “At this time our priority is to respect the privacy of the families and to allow investigators to conduct their work.”