MICHAEL Jackson's death has been ruled a homicide, according to media reports today.

The Associated Press said the Los Angeles County coroner had made the finding, but cited an unnamed law enforcement official.

Meanwhile, an official document has revealed Jackson died of "lethal levels" of the anesthetic propofol.

The details came from a search warrant affidavit released in Houston.

"The Los Angeles Chief Medical Examiner-Coroner, Dr Sathyavagiswaran, indicated that he had reviewed the preliminary toxicology results and his preliminary assessment of Jackson's cause of death was due to lethal levels of propofol (diprivan)," it said.

Jackson suffered cardiac arrest and died on June 25 at age 50.

Since then, police have probed his death in an investigation that appears focused on the use of prescription drugs and the role of doctors who treated him, including his personal doctor, Conrad Murray.

The search warrant document was released by the Harris County District Clerk in Houston, where Dr Murray has offices.