The son of an Alberta couple that went missing one year ago says he's still hopeful he'll find out what happened to his parents.

Lyle and Marie McCann went missing on July 3, 2010. Lyle, 78, and his wife, Marie, 77, left St. Albert, Alta., bound for British Columbia. They were last seen that day at a gas station in the city just west of Edmonton.

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

Despite an intensive investigation, police have found no sign of the missing couple.

Bret McCann said his parents are likely dead, but hopes they will be found soon.

'Awful and terrible fate'

"It's been a nightmare, as you can imagine. I mean, life still goes on ... but we're hanging in there. The police urge us just to be patient and we are," he said.

"We've accepted that my parents have met some awful and terrible fate, probably on that first day of July 3, but we're really hoping to bring some closure to this by finding out what happened to my parents and hopefully those responsible will be brought to justice."

Police and volunteers have conducted dozens of searches, and hundreds of tips have poured in from the public, to no avail.

McCann is hoping the anniversary of his parents' disappearance will bring attention to the case.

"With this long weekend here, people are going camping and so on; they may be going to the same area they went to last year … they may remember something from last year, either seeing my parents or seeing their motor home," he said.

"It's such a vast area there … we have no idea what happened, but probably something happened somewhere between Gainford and Edson, so that's a huge territory to look at, so any assistance the public can give would be invaluable."

Investigation moving forward

Police are still actively investigating the case.

"Our family meets with the police every six weeks or so," McCann said.

"We met with them last Monday and they had an investigator there who kind of described the whole investigation as very painstaking, very high-tech, but he's still pleased with the progress and sees the investigation still going forward, so we took a lot of reassurance from that."

McCann said the community support has been overwhelming, and has helped the family cope throughout the ordeal.

"I really get the sense that this has affected a lot of people. This could be anybody's parents or grandparents and I want people to know that we feel their support and it really helps us."

Police say they have persons of interest in the case but no arrests have been made.

Anyone with information is asked to contact their local RCMP detachment or Crime Stoppers.