MISSOULA, Mont. -

It's been almost 3 years since then-82-year-old Florence Dumontet and her toy poodle, Peaches, went missing.

Detective Dan Hillebrand came to Missoula in the spring of 2012. Now he's back to hand out reward posters and to keep looking for leads in Dumontet's disappearance.

"Originally everyone was really hopeful that she was just missing, but as time goes by, we are hitting that 3-year mark and she has not been located yet. There have been no sightings at all and no sightings of her vehicle. So she disappeared off the face of the earth," said Hillebrand.

Hillebrand and family members are worried because Dumontet had a specific route. She was driving from Ardoch, North Dakota, to Shelton, Washington, to visit her family. It's a route she'd driven many times before.

Surveillance footage shows Dumontet at a gas station in both Bismarck, North Dakota, and then in Butte. Surveillance footage also proves it's Dumontet because of the rare Lincoln Mark pickup truck she was driving.

While investigators say they know that's the last place she stopped, a witness claims he saw Dumontet at Muralt's gas station in Missoula. NBC Montana reached out to the witness but he didn't want to talk.

Hillebrand explained what the witness reported. He said Dumontet was looking to get her car fixed and that's when the witness says he directed her to a local Ford dealer.

The witness claimed she was with another woman, and the two appeared to be friends who were traveling together. Dumontet's family maintains her only companion was Peaches.

That's the last time anyone reported contact with her. Her truck never passed through the license plate reader on the Idaho and Washington state line.

There are no leads or suspects in the investigation, which is why Hillebrand is asking anyone with information to come forward.

"Any information is helpful, if you think you have a piece of information that's going to help, please call," said Hillebrand.

Hillebrand plans to travel back to North Dakota Saturday and make a stop in Butte to distribute the reward posters. The reward amount is being kept confidential by Dumontet's family.

If anyone has any information about Dumontet's whereabouts, they are asked to call the Grand Forks County Sheriff's office at (701) 780-8280.