Police in Los Angeles are testing a knife recovered on a property once owned by the former football star, OJ Simpson. br Someone claiming to be a construction worker gave an off-duty police officer the knife some years ago and he kept it, thinking the case was closed. br Simpson was acquitted of the murders of his ex-wife and her friend in June 1994. br Captain Andrew Neiman from the Los Angeles Police Department said the knife was now undergoing forensic tests.