UPDATE: Los Angeles Superior Court spokesman Allan Parachini confirms to E! News that three search warrants have been issued thus far in relation to the Jackson investigation. Parachini would not say what agency asked for the warrants or what they were for, but a Jackson insider says two of the warrants were related to last week's search of the entertainer's Holmby Hills home.
As investigators continue to dig into the mystery of Michael Jackson's death, new details are emerging constantly. A Jackson family source confirmed to E! News that there were needle marks on the singer's body, consistent with tales of drug injections, and at least four of Jackson's former doctors are facing intense scrutiny.
LAPD detectives, who are being assisted by the DEA, have a special interest in questioning Beverly Hills dermatologist Arnold Klein and are still focusing on Dr. Conrad Murray, according to the source.
Murray was with Jackson in his Holmby Hills mansion at the time of his death, and has already been questioned by police.
Klein, Jackson's longtime friend (and rumored biological father of Jackson's two oldest children) had not been questioned as of Friday afternoon. The source said investigators have been in contact with Klein's attorney, however.
The source also claims that police are probing at least two unidentified anesthesiologist who might have information about if and how the King of Pop was able to get his hands on the potent anesthetic Diprivan that was reportedly found at the mansion when he died.
Diprivan, which is generally administered by IV, has been one of the main drugs at the forefront in possible causes of Jackson's death.
The source also confirmed that needle marks were found on Jackson's body during the coroner's autopsy. While the source would not confirm where on the body the marks were, they were consistent with puncture wounds from injectable medications.
Reps for both Klein and Murray declined to comment today about their clients' possible knowledge of Jackson's drug use. Last week, Murray's lawyer insisted that his client was "not a suspect."
Jackson's family is still cooperating with police, according to the source.
(Originally published July 5, 2009, at 4:35 p.m. PT)
Be there as the world says goodbye to the King of Pop. Watch the Michael Jackson memorial on Tuesday at 1 p.m. ET/10 a.m. PT live on E! and E! Online