Friends and family of a missing B.C. couple are keeping hope alive, but the only promising lead in the case has turned out to be a dead end.

Al and Rita Chretien left Penticton on March 19 in their Chevrolet Astro van, bound for a trade show in Las Vegas. They never showed up, and were last seen on surveillance video at a gas station in Baker City, Oregon on the day they left home.

Six close friends of the couple are now helping police in Oregon search for the Chretiens.

Their first step was to check out a lead -- the couple apparently visited a Yamaha dealership in Baker City as well, and told staff they'd visited a nearby interpretive centre.

But searchers have discovered the Chretiens' names don't appear in the guest book at that interpretive centre.

That means the search team is heading out to scour thousands of kilometres of highway to search for the missing couple, stopping anywhere the vehicle might have gone off the road.

"You're looking for tracks that go off the side or trees that have been damaged," Al's brother-in-law Tim Hoving said.

It's a daunting task, but the Chretiens' friends say they have to keep looking.

"Al and Rita would have done that for us if we were on the other side of the fence," family friend Armand Gregoire said.

Al's sister Lorraine Hoving says she isn't ready to give up.

"You never lose hope that you can find them and you can still find them alive. It would take a miracle now, but we still believe in miracles," she said.

The Chretiens' friends are planning for one more day of searching before they head home.

With a report from CTV British Columbia's Kent Molgat