The LAPD has recovered a knife believed to have been found on O.J. Simpson's former property, and held by a now-retired police officer for several years.

Police say a construction worker claimed he recovered the knife from Simpson's property at the time the home was being demolished, and handed it over to an off-duty traffic officer who was working on a movie shoot in the area. The officer, who may have been retired at the time, did not report the discovery and kept the knife for himself, police said.

The officer, who is believed to have retired some time in the late 1990s, turned the knife in sometime in the last month. It’s unclear when the item came into his possession.

Capt. Andrew Neiman, of the LAPD's media relations section, said he was "shocked" to learn of the discovery, and the length of time it went unreported. He said an officer "would know that any time you come into contact with evidence, that you should submit that to investigators."

Investigators learned of the item and recently recovered it from the former officer, Neiman said. Police are now exploring the possibility of charges.

Simpson was acquitted of two murder charges in a highly publicized trial in 1995, for the deaths of his ex-wife, Nicole Brown Simpson, and her friend, Ronald Goldman. The two were found stabbed to death outside Brown's residence on June 13, 1994.

Investigators were not able to positively identify the murder weapon at Simpson's criminal trial.

Neiman said the knife is being treated as evidence in the case, and is undergoing forensic testing. He added that the case remains open, as no killer has been identified. However, Simpson will likely not face the same murder charges again, as it would be considered double jeopardy, Neiman understood.

Police did not indicate the size or make of the knife, saying only that it is "not a machete."

Simpson is currently serving time behind bars for a botched hotel room heist in 2007, and is not eligible for parole until next year.