The Associated Press

LOS ANGELES (AP) -Search warrants served at the Las Vegas home and office of Michael Jackson's doctor show investigators think the pop star was an addict.

The warrants, served Tuesday and filed in court Thursday, targeted Dr. Conrad Murray. They say investigators wanted to seize any evidence relating to the sale and shipment of the powerful anesthetic propofol (PROH'-puh-fahl).

The warrants say authorities were seeking evidence supporting a manslaughter charge and medical rule infractions including "prescribing to an addict."

A law enforcement official has said investigators are working under the theory propofol caused Jackson's heart to stop. The official spoke on condition of anonymity because the investigation is ongoing.

Associated Press Writer Ken Ritter in Las Vegas contributed to this report.