By Ryan Felton
DETROIT (Reuters) - In the latest twist in the 37-year-old search for missing Teamsters union boss Jimmy Hoffa, police said on Tuesday a soil sample taken from behind a suburban Detroit house did not contain human remains.
"As a result of these tests the Roseville Police Department will be concluding their investigation into the possible interment of a human body upon the property," Roseville Police Chief James Berlin said in a statement.
Berlin said a battery of tests were conducted and "the samples submitted for examination showed no signs of human decomposition."
Police acting on a tip that a body might be buried there, drilled through concrete and took a soil sample from under a shed behind a house on Friday. Police said before the search that they did not believe any body, if there was one, was that of Hoffa.
The disappearance of Hoffa in July 1975 in what authorities believe may have been an organized crime hit, has sparked thousands of leads, but no remains have been found.
Hoffa's dramatic life story inspired a 1992 movie "Hoffa" starring actor Jack Nicholson.
Berlin had said previously that authorities had tried to keep the dig low-key and were treating it as a possible cold-case homicide, not a search for Hoffa.
Police were obligated to follow through on what appeared to be a credible tip. An informant believed he had seen someone buried there at about the time Hoffa disappeared, though there were "inconsistencies" in the tipster's timeline, Berlin said last week.
The Michigan environmental quality department had used ground-penetrating radar on the site and detected "anomalies" that required authorities to take a soil sample.
More than a hundred onlookers, including camera crews from local TV stations and curious neighbors, watched on Friday from behind yellow tape as investigators took the sample from inside a large backyard shed.
Hoffa, the father of current Teamsters President James Hoffa, led the union from 1957 to 1971, spending the final years of his term in prison for fraud and jury tampering. He was released in late 1971 when President Richard Nixon commuted his sentence.
Authorities have long believed that Hoffa was ordered killed by organized crime figures to prevent him from regaining control of the Teamsters. He had agreed to be banned from the union until 1980 as part of the deal that got him out of prison.
(Writing by David Bailey; Editing by Greg McCune and Jackie Frank)