The FBI says it found no sign of the body of missing Teamsters boss Jimmy Hoffa under a bridge in New Jersey.
Agents conducted the latest search for the remains of Hoffa, who vanished in July 1975, on land next to a former landfill that sits beneath the state’s Pulaski Skyway.
“Nothing of evidentiary value was discovered during that search,” said Mara Schneider, an FBI spokeswoman in Detroit.
“While we do not currently anticipate any additional activity at the site, the FBI will continue to pursue any viable lead in our efforts to locate Mr Hoffa.”
Hoffa disappeared after he was due to meet with Detroit mob enforcer Anthony “Tony Jack” Giacalone and alleged New Jersey mob figure Anthony “Tony Pro” Provenzano at a restaurant in suburban Detroit.
The FBI search in New jersey was linked to interviews given by Frank Cappola, who as a teenager in the 1970s worked at the PJP Landfill in Jersey City with his father.
Mr Cappola has said that in 2008, his dying father, Paul Cappola, told him that Hoffa’s body was taken to the landfill where it was put in a steel drum and buried with other barrels.
Journalist Dan Moldea, who has written about Hoffa’s disappearance, says that Paul Cappola was worried about police surveillance and dug another hole on New Jersey state property near the landfill and reburied the barrel there.
Mr Moldea says he was contacted by the FBI about their search last year and was told about their lack of success on Thursday.
He told the Associated Press that agents had not dug in the exact spot he had told them to.
“I’m not thrilled with the result... My impression today was them breaking the bad news to me: Thanks for the tip but this is over. That’s my interpretation,” Mr Moldea told the news organisation.
Hoffa was president of the 2.1 million-member Teamsters union from 1957-71, even keeping the title while in prison for trying to bribe jurors during a previous trial. He was released from prison in 1971 when President Richard Nixon shortened his sentence.
It has been long speculated that Hoffa, who was 62, was killed by enemies because he was planning a Teamsters comeback. He was declared legally dead in 1982.
The Associated Press contributed to this report.