A county coroner's official visited the office of Michael Jackson's dermatologist on Tuesday to follow up on a subpoena seeking additional medical records.
Assistant Chief Coroner Ed Winter said outside the Beverly Hills office of Arnold Klein that the doctor had been cooperating in the investigation.
Winter showed up at Klein's office after the doctor failed to provide records he'd promised to give authorities when they first requested them on July 2, according to TMZ. The site reported that Klein's lawyer sent over partial medical records and promised the rest, but never delivered them. When Winter's office called Klein's to say they had not received the documents, the doctor's reps reportedly never responded.
Klein's attorney, Richard Charnley, said in a statement that his client will provide the documents Wednesday.
Craig Harvey, the coroner's chief of operations, would not specify what records were being sought.
Investigators have focused on the role drugs may have played in Jackson's death.
In recent TV interviews, Klein said he had sedated Jackson for past medical procedures. He denied ever giving the pop star an unnecessary dose of drugs.
An official cause of Jackson's death has not yet been determined, as authorities await the results of toxicology tests, which are said to be due within the next week. Among the focuses of the investigation is the role the powerful anesthetic Diprivan may have played in Jackson's death. Numerous outlets have reported that police investigators found the drug at Jackson's home and several sources, including Klein, have said the singer used the drug to combat chronic insomnia.