LOS ANGELES (AP) — After nearly a month of testing, Los Angeles police detectives have concluded a knife found at the former estate of O.J. Simpson was not the weapon used to kill Simpson's ex-wife Nicole Brown Simpson and her friend Ronald Goldman in 1994.

Investigators ruled out the knife after weeks of forensic tests, Police Capt. Andy Neiman said Friday. "We have confirmed, we have determined, there is no nexus," he said.

Police revealed last month they had recently discovered the knife had been in the possession of a retired Los Angeles police officer for more than a dozen years. The officer said he received it from a construction worker who told him he had found it while working on a crew tearing down Simpson's old Brentwood estate.

Simpson was acquitted of stabbing to death his wife and Goldman on June 12, 1994, outside her condominium, which was not far from the estate.

Over the years, police have examined several knives, but have never found one they could connect to the killings.

Simpson, meanwhile, has steadfastly maintained that he did not kill his wife and her friend.

He is serving a sentence of nine to 33 years in a Nevada prison for a bungled 2007 Las Vegas hotel robbery in which the former football star tried to retrieve sports memorabilia he said had been stolen from him. After the items were seized from memorabilia dealers held at gunpoint, he was convicted of robbery and kidnapping. He is eligible for parole next year.

Investigators previously said it was unlikely this knife was the murder weapon, noting it was too small to inflict the damage the victims suffered.

A lawyer for retired Officer George Maycott has said the construction worker gave his client the knife after meeting him on a film set where the officer was providing security.

Attorney Trent Copeland said his client, who by then had retired, attempted to hand the knife over to the LAPD, but he was told there was no need because Simpson had been acquitted.