One Year Later: Why Won't Father Tell All About Missing Sons?

John Skelton is serving hard time for abducting his three sons, but one year later he still won't tell police more about the missing boys' fates.

Authorities have found no trace of Tanner, Alexander and Andrew – who ranged in ages from 5 to 9 – and their father's no-contest plea to false imprisonment has gotten investigators no closer to answers.

"Certainly there's frustration," Morenci, Mich., Police Chief Larry Weeks tells PEOPLE. "We have three boys out there that are missing, and he doesn't seem willing to provide us with factual information about where they're located."

After the boys' disappearance, police identified Skelton as a suspect and determined that he got rid of the boys on the morning after Thanksgiving in 2010.

"We know he left his home 4:29 a.m. the morning after Thanksgiving and returned at 6:46," Weeks says. "It's during that time that we believe that he disposed of them in some fashion."

Skelton has provided various accounts of what he did with the boys.

He said he gave them to a pastor's wife named Joann Taylor, because he was going to commit suicide. Then he said he gave them to an unnamed underground organization to protect them from abuse by their mother, Tanya Zuvers.

Cleared by authorities of any wrongdoing. Zuvers has told PEOPLE that she doesn't understand her former husband's unusual behavior.

Skelton has never been tried for harming the boys. Over the summer, he pleaded no contest to three unlawful imprisonment charges and was sentenced to 10 to 15 years.

Skelton maintains that he's unable to contact the organization that he claims took the boys and he doesn't know where they're being kept.

"He says that they're alive and they'll be back when they're old enough, when there won't be a … danger of abuse by their mother," says his attorney John Glaser. The lawyer declined to comment as to whether he believes his client.

Investigators, however, are skeptical that the boys are alive after finding a noose in Skelton's house and a search for "neck breaking" on his computer.

Their unsolved disappearance has been traumatic for the whole community of Morenci, which is at the southern edge of Michigan, about 40 miles west of Toledo, Ohio.

Hundreds of people gathered Nov. 27 at the Morenci High School gym to remember the boys and to remind the country that there is a $60,000 reward for information leading to their recovery or return.

The crowd wept as family members and friends read poems, sang and played a slideshow of the brothers. They also unveiled a plaque of the boys that was to be fastened to a rock at a local park.

Addressing the audience, Zuvers urged people "to keep those prayers going. Let's not have to do this in another 365 days."

Five Things We Know About Next Summer's Bourne Legacy

 Considering you can watch The Bourne Identity, Bourne Supremacy and Bourne Ultimatum in their entireties and still not know exactly what's going on, we'll take any head start on Bourne story-mapping that we can get.

And while the true mysteries of The Bourne Legacy, the fourth film in the spy-thriller franchise and the first to not feature Matt Damon's Jason Bourne, will probably have to be pried out of a confidential informant's cold, dead hands, we have learned a few things about the top-secret flick, courtesy of its new leading man, Jeremy Renner.

Don't worry, no informants were injured in the compiling of this list:

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1. Hot Stuff: The Bourne Legacy is due in theaters Aug. 3, 2012, where it will battle for box office supremacy opposite the Total Recall remake starring Colin Farrell, Kate Beckinsale and Jessica Biel. Along with Renner, the Bourne sequel stars Rachel Weisz and Edward Norton. Surely this makes for enough hotness to satisfy all moviegoers that weekend.

2. Can I See Some ID, Please: For all intents and purposes, Renner plays put-upon CIA spy Aaron Cross. But, considering the way the ball bounces in the Bourne series, Cross "ends up having a bunch of different names," Renner told EmpireOnline.

3. Blink and You'll Miss It: While The Bourne Legacy novel, the first in the series by Eric Van Lustbader, who took over after Robert Ludlum died, again centers on Jason Bourne, Damon's exit from the franchise prompted the creation of a new character, rather than a recast. The novel features Bourne/David Webb getting sucked back into the spy biz after an assassin's bullet narrowly misses him. Then he's framed for murder and out come the Chechen terrorists, a dirty bomb, secret spawn and all sorts of plot twists. How will they adapt this for the big screen with a different main character? Well, Renner says, the film will have "that same ticking clock" that fans of the Bourne films expect. And that's all we get for now.

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4. The Big Bad: The nefarious Treadstone—the black ops program that made Jason Bourne into a wily assassin—is still in play, according to Renner. Or is it? In fact, we've heard that the folks who brainwashed Aaron Cross are even more dangerous than the control freaks behind Treadwell. Renner says Legacy features the "same deal" but with "a new set of agents with a different leash." Called Operation Blackbriar? Operation Mistletoe? Operation Buzz Cut? What?!

5. Role Call: Drive star Oscar Isaac, who tested for Renner's role, has been relegated to the still very pivotal role of an assassin known as "Number 3." Meanwhile, because behind every great man is a great woman, that's where Weisz fits in. And Norton is set to play a presumably very crafty villain who doesn't want to rest until he sees Aaron Cross (or whatever his name really is) dead.