Michael Jackson's Private Doc Still Solo Subject of Investigation

Despite interest in his communications with other Jackson docs, law-enforcement source says only Dr. Conrad Murray is being investigated

Authorities may want to know all about the different types of medical treatment Michael Jackson received in recent years—but they're still zeroing in on only one particular physician.

A law-enforcement source close to the increasingly convoluted investigation into Jackson's death exclusively tells E! News that cardiologist Conrad Murray remains the only doctor at the center of the Los Angeles Police Department's manslaughter investigation, despite the interest in any correspondence the doc may have had with six other medical professionals who once counted Jackson as a patient.

"We're just focusing on Murray at this time," the source said. "It's a nightmare as it is. The issue may come up again, but right now the focus is on Murray."

Included on the search warrant served on Murray's home and offices in Las Vegas Tuesday were records of correspondence between him and/or Jackson and six other doctors, including rheumatologist Allan Metzger and dentist Mark Tadrissi, both of whom have been asked to turn their Jackson files over to the L.A. County Coroner's Office.

Metzger's attorney, Harland Braun, confirmed to E! News that Jackson once asked his client for propofol—the potent anesthetic authorities believe ultimately caused the singer's death—to help him sleep, but that Metzger refused to provide any.

"Dr. Metzger tried to warn him it was dangerous and turned him down," Braun said, adding that there has been no indication that his client, who was subpoenaed by the coroner's office today, is a target of a criminal investigation.

Tadrissi, a cosmetic dentist, opted not to comment when reached by E!

Coroner's investigators have also paid visits to Jackson's former nutritionist, nurse Cherilyn Lee; dermatologist Arnold Klein; anesthesiologist Randy Rosen; and ear, nose and throat specialist David Slavit, all of whom were listed on the search warrant.

Klein, Metzger and Lee are said to have been in contact with Jackson shortly before his death. Murray was employed as the Thriller artist's personal physician and was the one who discovered Jackson unconscious in his Holmby Hills mansion on June 25.

"Dr. Murray doesn't have any professional or personal association with any of the doctors listed in that search warrant," the cardiologist's attorney, Edward Chernoff, said Thursday. Chernoff has said that Murray did not administer any drug to Jackson that would have resulted in his death.

Meanwhile, all the twists and turns have prompted the coroner's office to indefinitely delay the release of Jackson's autopsy results as authorities continue piecing the puzzle together.

And as we're sure you've noticed, there are a lot of pieces.

(Originally published July 31, 2009, at 9:33 p.m. PT)