Marie and Lyle McCann were last seen July 3. (RCMP)

RCMP confirmed Friday they are searching a piece of private property south of Nojack, Alta., in their investigation into the disappearance of a missing Alberta couple.

Lyle McCann, 78, and his wife, Marie, 77, left St. Albert, Alta., on July 3 bound for British Columbia. They were last seen that day at a gas station in the city just west of Edmonton.

RCMP said the search started on Friday morning.

The McCanns' son Bret said he has mixed feelings about the search.

"Apprehension … what are they going to find?" he said. "But also I guess I'm pleased the police investigation is proceeding and I have to view it as getting one step closer, another step closer to finding my parents."

The RCMP named Travis Vader, an Alberta man, as a suspect in the case on Aug. 31 but no charges related to the McCann investigation have been laid.

They will not say what led them to search the property near Nojack, a town about 140 kilometres west of Edmonton.

Reward now at $60,000

The McCanns left St. Albert, Alta., on July 3 headed for British Columbia. The couple was driving a motorhome, which was towing their green Hyundai Tucson SUV.

They were reported missing on July 10 after they failed to meet up with their daughter in Abbotsford.

RCMP later confirmed that a burned-out motorhome found in a campground on July 5 belonged to the McCanns. They found the Tucson in a wooded area near Edson, Alta., on July 16, the same day they declared Vader a person of interest.

Vader was arrested the following week and remains in custody on unrelated charges.

Earlier on Friday, the McCann family announced the reward for a tip that solves the missing persons case is now $60,000, thanks to people who donated to a fundraising campaign.