The rusty knife supposedly found during the demolition of O.J. Simpson's former Brentwood home and kept by a police officer for years "has no nexus to Simpson/Goldman murder investigation," Los Angeles Police said Friday.

Cold case investigators got the knife several weeks ago and conducted tests on it after a retired police officer revealed he was given it by a man who was helping tear down the Simpson house in 1998.

#LAPD has determined knife has no nexus to Simpson/Goldman murder investigation. The investigation remains open

-- LAPD Online News (@LAPDonlinenews) April 1, 2016

Investigators never found a murder weapon in the Nicole Brown Simpson and Ronald Goldman killings.

The LAPD says the case is still open, although Simpson is protected from being charged again for the killings because he was found not guilty after a lengthy and controversial murder trial.