Charlie Sheen is being investigated by the Los Angeles Police Department for allegedly threatening to kill his ex.

FOX's Jessica Rosenthal reports from Los Angeles.:

LAPD officer Mark Lopez confirms a criminal investigation in which Charlie Sheen is listed as the suspect.

(Lopez) "LAPD threat management unit detectives are the lead investigators on the case. Our victim's information is confidential based on the crime that occurred."

He did say a search warrant has been served, now RadarOnline says they were served over articles they wrote based on an audio tape that a print tabloid claims to have where Sheen is allegedly heard making threats about his ex fiancee's life.

Scottine Ross sued Sheen last year alleging he was violent and exposed her to HIV when they were together. This month she reportedly got a restraining order which an attorney for Sheen called a publicity stunt.

Jessica Rosenthal, FOX News.