Updated

The owner of the construction company that razed O.J. Simpson’s former Los Angeles estate where a knife was found buried in the ground wasn’t fazed by the report Friday.

“I think it’s a joke. I think it’s just filler. No one on my crew found anything, Mike Weber, owner of Weber-Madgwick Inc., told the Los Angeles Times. “I had instructed my people, ‘if you find anything, don’t keep it. Tell me, we’ll take appropriate action.’”

The construction crew spent six weeks tearing down the home where Simpson lived at the time of the murders of Nicole Brown Simpson and Ron Goldman in 1998. Jobs were being done at the property for at least two years as a new home was being built, Weber said.

“Hundreds and hundreds of people were there after me,” he added.

Fox News confirmed earlier Friday that the knife was undergoing forensic testing. TMZ reported a construction worker found the knife years ago and gave it to an off-duty cop who kept it in his home before finally turning it over to police in January.

Law enforcement sources told TMZ the blade is a folding Buck knife. It's now being tested for hair and DNA after it was handed over to the LAPD’s Robbery and Homicide Division.

"It is being treated as we would all evidence," LAPD Capt. Andy Neiman said Friday. He added that police were "quite shocked" to learn about the knife after so many years.

Since the news of the knife was revealed, Weber said he was receiving tons of emails from friends with links to when he told media reporters he was looking for the knife.

“Jokingly, I said I was looking for the knife. And that’s not just being flippant. We never found it,” Weber added.

Simpson's property was in the Brentwood section of LA. In 1995, a jury found him not guilty of murder after the so-called "Trial of the Century" dominated the media for months. Nicole Brown Simpson and Ron Goldman, her friend, were found stabbed to death in June of 1994.

In 1997, a jury found Simpson civilly liable for the slayings. He's now imprisoned in Nevada on a robbery-kidnap conviction.

The weapon used in the killings has been a mystery for decades.

NBC News, citing unnamed law enforcement officials, reported that it was a smaller, relatively inexpensive utility-style blade typically carried by construction workers or other laborers and inconsistent with it being the murder weapon.

"We discovered it and our investigators immediately followed up on it," Neiman added. Simpson likely cannot be prosecuted again for the stabbings because of constitutional protections against being charged for the same crime twice, or double-jeopardy.

One source told TMZ the knife appeared to have blood residue on it, but it’s extremely rusted and stained, requiring further testing.

The cop who kept the knife, an officer assigned to the traffic division, was off-duty at the time and never alerted higher-ups to the discovery, TMZ reported.

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LOS ANGELES - MARCH 16: O.J. Simpson and Nicole Brown Simpson pose at the premiere of the "Naked Gun 33 1/3: The Final Isult" in which O.J. starred on March 16, 1994 in Los Angeles, California. (Photo by Vinnie Zuffante/Archive Photos/Getty Images) (1994 Getty Images)

In late January the cop reportedly contacted a friend in the homicide division and told him he was getting the knife framed for his wall.

According to TMZ, the cop even asked his friend to get the department’s record number for the Simpson-Goldman murder case so he could engrave it in the frame. He was forced to surrender the knife to LAPD when the friend told superiors.

Sources told TMZ authorities are keeping their investigation top secret and under wraps, even logging the case into a computer system outside the official case file.

The Associated Press contributed to this report.

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