NIAGARA COUNTY, N.Y. - In an effort to solve one of Western New York's oldest missing persons cases, investigators have now conducted 35 new interviews related to the disappearance of Russell Mort, the two-year-old boy last seen in his backyard in Wheatfield in 1982.

The Niagara County Sheriff's Office announced in 2015 it would collaborate with the FBI's Cold Case Working group to reinvestigate the case. Since then, the agencies have made significant progress, according to Undersheriff Michael Filicetti and investigator John Wick.

Wick, considered the lead investigator on the Mort case, said the 35 interviews have in turn generated new interviews and new leads for the Sheriff's Office and the FBI.

"I think we're moving in the right direction to find out what happened," Wick said. "My heart goes out to the Mort family, because we want to find out the truth, and I know they do as well."

As a part of the investigation, law enforcement have been attempting to recanvass and recreate the Lynch Park neighborhood, where Mort disappeared from in 1982. They also created a hotline for people to call with tips.

Filicetti said the Mort case weighs heavily on the Niagara County Sheriff's Office, but the FBI's involvement in the case has made him optimistic.

"The FBI has been a tremendous partner of ours in this investigation," Filicetti said. "They've provided us with resources, things we just don't have at the Sheriff's Office."

In Nov. 2015, as a part of a broader 2 On Your Side story about long-term missing persons cases, FBI Special Agent in Charge Adam Cohen said the purpose of the Cold Case Working Group was to bring a fresh perspective and new technology to investigations that may have stagnated.

"We recognize the fact that this is important," Cohen said. "(These cases) are very important to the people that we're supposed to be serving, so we're going to dedicate the resources that we can."

Wick said it's been gratifying to make progress on the case.

But he wants to deliver closure to the Mort family.

"They deserve to know the truth," Wick said, "and we intend on trying to bring that to them."

Anyone with information on the case may call the Niagara County Sheriff's Office at 716-438-3393. Callers are encouraged to ask for investigator John Wick.