Story highlights Teamsters boss Jimmy Hoffa disappeared on July 30, 1975

A man connected with Detroit's organized-crime family says he knows where Hoffa was buried

A former prosecutor says, "This is a man who would have been in the know"

The FBI declines to comment on the man's claims

A man convicted of crimes in connection with Detroit's organized-crime family claims to know where Teamsters boss Jimmy Hoffa's body was buried in 1975.

Anthony Zerilli, 85, told New York's NBC 4 that Hoffa was buried in a Michigan field about 20 miles north of where he was last seen on July 30, 1975.

"I'm as certain as I could possibly be," Zerilli told the station. "If I had money, I'd like to bet a big sum of money that he's buried (there)."

Zerilli said the plan was to bury Hoffa in a shallow grave, then move his body to a different location. The latter part of the plan fell through, and his body was left in Oakland County, Michigan.

In an interview with CNN on Monday, former U.S. attorney and chief of the Eastern District of Michigan's Organized Crime Strike Force Keith Corbett said there are very few people, if any, who would be more likely to know about Hoffa's disappearance than Zerilli.

Photos: Photos: The mystery of Jimmy Hoffa Photos: Photos: The mystery of Jimmy Hoffa The mystery of Jimmy Hoffa – Nearly 40 years after his disappearance, former Teamsters boss Jimmy Hoffa, pictured circa 1955, remains among America's most famous missing persons. Authorities have been searching for the once powerful union boss since he vanished in 1975. Hide Caption 1 of 21 Photos: Photos: The mystery of Jimmy Hoffa The mystery of Jimmy Hoffa – Hoffa slumps in a chair at the Teamsters union office. He was one of the most powerful union leaders in America until being forced out of the organized labor movement. He went to prison in 1967 for jury tampering and fraud before being pardoned four years later. Hide Caption 2 of 21 Photos: Photos: The mystery of Jimmy Hoffa The mystery of Jimmy Hoffa – Hoffa appears at the Teamsters union convention in 1957, the year he first became union president. Hide Caption 3 of 21 Photos: Photos: The mystery of Jimmy Hoffa The mystery of Jimmy Hoffa – Hoffa, center, stands with other officials at the Teamsters convention, where he made a successful bid for control of the union in 1957. Hide Caption 4 of 21 Photos: Photos: The mystery of Jimmy Hoffa The mystery of Jimmy Hoffa – Hoffa testifies at a Senate Rackets Committee hearing in 1958. Hide Caption 5 of 21 Photos: Photos: The mystery of Jimmy Hoffa The mystery of Jimmy Hoffa – Hoffa on the phone at an airport in 1959. Hide Caption 6 of 21 Photos: Photos: The mystery of Jimmy Hoffa The mystery of Jimmy Hoffa – An office for Teamsters union local chapters that Hoffa set up. Hide Caption 7 of 21 Photos: Photos: The mystery of Jimmy Hoffa The mystery of Jimmy Hoffa – Hoffa eats with union leader Joseph Curran, left, in 1959. Hide Caption 8 of 21 Photos: Photos: The mystery of Jimmy Hoffa The mystery of Jimmy Hoffa – Hoffa holds a Teamsters rally at Madison Square Garden in New York in 1960. Hide Caption 9 of 21 Photos: Photos: The mystery of Jimmy Hoffa The mystery of Jimmy Hoffa – Hoffa leads supporters at a Teamsters convention in 1959. Hide Caption 10 of 21 Photos: Photos: The mystery of Jimmy Hoffa The mystery of Jimmy Hoffa – The Teamsters boss appears on the cover of Life magazine on May 18, 1959. The headline reads, "A National Threat: Hoffa's Teamsters; Part 1: Sources of a Union's Uncurbed Power." Hide Caption 11 of 21 Photos: Photos: The mystery of Jimmy Hoffa The mystery of Jimmy Hoffa – Hoffa, pictured circa 1960, was a powerful labor leader at a time when unions wielded a great deal of sway over elections and were notoriously tied to organized crime. Hide Caption 12 of 21 Photos: Photos: The mystery of Jimmy Hoffa The mystery of Jimmy Hoffa – From left, "Meet the Press" moderator Ned Brooks, Lawrence K. Spivak and Hoffa appear at an NBC studio. Hide Caption 13 of 21 Photos: Photos: The mystery of Jimmy Hoffa The mystery of Jimmy Hoffa – Hoffa and his son, James Phillip, enter a federal courtroom in July 1964. His son is the current president of the Teamsters. Hide Caption 14 of 21 Photos: Photos: The mystery of Jimmy Hoffa The mystery of Jimmy Hoffa – Hoffa, second row, center, leaves court after being found guilty of jury tampering in 1964. Hide Caption 15 of 21 Photos: Photos: The mystery of Jimmy Hoffa The mystery of Jimmy Hoffa – Hoffa at the Pittsburgh airport in 1971 on his way back to federal prison after being let out to visit his ailing wife. He was released from prison later that year on the condition he not resume union activity before 1980. Hide Caption 16 of 21 Photos: Photos: The mystery of Jimmy Hoffa The mystery of Jimmy Hoffa – Hoffa poses for a picture on July 24, 1975, less than a week before his disappearance. He was 62 at the time. Hide Caption 17 of 21 Photos: Photos: The mystery of Jimmy Hoffa The mystery of Jimmy Hoffa – A Bloomfield Township, Michigan, police officer stands beside Hoffa's car after the former labor leader's disappearance in July 1975. Hoffa was last seen at a restaurant in suburban Detroit on July 30, 1975. Hide Caption 18 of 21 Photos: Photos: The mystery of Jimmy Hoffa The mystery of Jimmy Hoffa – Police sweep a field in Waterford Township, Michigan, in search of Hoffa's body in July 1975. Hide Caption 19 of 21 Photos: Photos: The mystery of Jimmy Hoffa The mystery of Jimmy Hoffa – Demolition workers tear down a horse barn for the FBI in 2006 in a search for Hoffa's remains in Milford, Michigan. The FBI had received a tip that Hoffa was buried on the farm. Hide Caption 20 of 21 Photos: Photos: The mystery of Jimmy Hoffa The mystery of Jimmy Hoffa – FBI agents search a field for Hoffa's remains on Monday, June 17, 2013, in Oakland Township, Michigan, outside Detroit. Alleged mobster Tony Zerilli tipped off the police, and a source close to the case said the information provided was "highly credible." Hide Caption 21 of 21

"Tony Zerilli was in a very high position within the Detroit organized crime family for decades," Corbett said. "This is a man who would have been in the know about all matters, especially what happened to Jimmy Hoffa."

Corbett, who prosecuted Zerilli in several cases in the 1980s and '90s, says Zerilli was the head of the Detroit organized crime family from 1970-1975, but was in prison himself when Hoffa disappeared.

In 2005, Zerilli was sentenced to 71 months in prison for racketeering and extortion. He was released in 2008.

In his interview with NBC 4, Zerilli denied playing any part in Hoffa's disappearance, and said Hoffa did not deserve what happened to him.

"If I wasn't away (in prison) I don't think it would have ever happened," Zerilli told the station. "That's the only thing I can tell you."

The FBI declined to comment on Zerilli's claims.

Corbett, however, told CNN he thinks the FBI will be taking Zerilli's words seriously, and will likely see if they can acquire a search warrant for the property in Michigan.

Hoffa's disappearance and presumed death has vexed investigators for almost four decades. As recently as October, soil samples were taken from a home in the suburban Detroit community after a tipster claimed he saw a body buried in the yard a day after Hoffa disappeared in 1975.

One of the most powerful union leaders at a time when unions wielded a great deal of sway in many elections -- and when some unions were notoriously tied to organized crime -- Hoffa was forced out of the organized-labor movement when he went to federal prison in 1967 for jury tampering and fraud.

Then-President Richard Nixon pardoned him in 1971 on the condition that he not try to get back into the union movement before 1980.

Hoffa, then 62, was last seen on July 30, 1975, outside a Detroit-area restaurant.

He was there ostensibly to meet with reputed Detroit mob enforcer Anthony Giacalone and Genovese crime family figure Anthony Provenzano, who was also a chief of a Teamsters local in New Jersey. Giacalone died in 1982; Provenzano died in 1988 in prison.

Hoffa believed Giacalone had set up the meeting to help settle a feud between Hoffa and Provenzano, but Hoffa was the only one who showed up for the meeting, according to the FBI.

Giacalone and Provenzano later told the FBI that no meeting had been scheduled.

The FBI said at the time that the disappearance could have been linked to Hoffa's efforts to regain power in the Teamsters and to the mob's influence over the union's pension funds.

"I'd like to just prove to everybody that I'm not crazy," Zerilli told NBC 4.

"What happened, happened while I was in jail, and I feel very, very bad about it ... (it) should have never happened to Jim Hoffa."