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FBI: Tip on Jimmy Hoffa prompts search

Teamster boss last seen July 1975 at a Michigan restaurant

(CNN) -- FBI agents and local police were searching a Michigan horse farm Wednesday for the remains of former Teamsters union leader Jimmy Hoffa after receiving a tip about his disappearance, the agency said.

The search was being conducted in Milford Township, 30 miles west of Detroit. Police from nearby Bloomfield Township were assisting the FBI agents.

A federal law enforcement official speaking on condition of anonymity said the search is for Hoffa's body.

Aerial footage from the scene showed at least 15 people outside a barn, most of whom were digging a rectangular hole.

The agents and local police were looking for "evidence of criminal activity that may have occurred when the properties were under previous ownership," FBI agent Daniel Roberts said in a news release.

"The search warrant is based on a lead which is one of numerous leads received through the years following the disappearance of Mr. Hoffa on July 30, 1975," he said.

John and Deb Koskovich have lived on a neighboring property since 1985. When they saw the men digging next door, John Koskovich asked them what they were doing.

"They just said they were executing a search warrant," Deb Koskovich said.

John Koskovich said there have been reports over the years that Hoffa may be buried in the area, but "we just thought it was just another one of those crazy rumors," he said.

Hoffa was last seen at Machus Red Fox restaurant in Bloomfield Township. He was reportedly there to meet Detroit mob street enforcer Anthony Giacalone and New Jersey Teamsters official Anthony Provenzano.

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 Hoffa's disappearance could have been linked to the union boss's efforts to regain power in the Teamsters after he was released from prison.

After serving time for jury tampering and fraud at a federal penitentiary in Lewisburg, Pennsylvania, Hoffa was pardoned by President Richard Nixon on December 23, 1971.

Nixon included in the pardon a condition that Hoffa "not engage in direct or indirect management of any labor organization" until at least March 1980.

Hoffa was 62 at the time of his disappearance.

In May 2004, authorities in Oakland County, Michigan, removed floorboards from a Detroit home and found blood that they thought might be linked to Hoffa's disappearance. Milford Township is in Oakland County.

Authorities went to the Detroit home in 2004 after a biography of former Teamsters official Frank Sheehan stated that Sheehan shot Hoffa in the home, just beyond the front door.

Investigators ruled blood found in the house was not Hoffa's. The FBI has a sample of his DNA.

Sheehan, who was considered a confidant of Hoffa's, died in December 2003. Provenzano died in 1988 after being convicted in another murder case and Giacalone died of kidney failure in 2002 at age 82.

Hoffa's son, James P. Hoffa, is the current president of the Teamsters.