The knife found on O.J. Simpson's old property and revealed to us a few weeks ago is not the knife.

FOX's Jessica Rosenthal reports:

The small knife found on the old Brentwood property is done being forensically tested and it's not the knife.

The LAPD confirmed in a Twitter statement. In their tweet they also say the investigation into the murders of Nicole Brown and Ron Goldman remains open.

A retired LAPD officer recently had turned it over. He said a construction worker who was on Simpson's old property back in the late 90's gave it to him in 2003 while the officer was working a movie set. His attorney said he tried to ask officials at the LAPD what he should do with it and was told they weren't interested in it. So he kept it in a toolbox all this time.

Jessica Rosenthal, FOX News.