LAS VEGAS, Nevada (CNN) -- Investigators began searching the Las Vegas home and office of Michael Jackson's personal physician, Dr. Conrad Murray, on Tuesday morning, a Drug Enforcement Administration spokesman said.
Los Angeles police and DEA agents, carrying search warrants, were "looking for a lot of things," said Assistant Special Agent in Charge Mike Flanagan.
Aerial cameras showed Las Vegas police cars were parked outside Murray's home and the residential street was closed. A CNN producer saw a police detective and a DEA agent enter Murray's medical office.
The searches come a day after a source with knowledge of the investigation confirmed to CNN that Murray administered a powerful drug that authorities believe killed the singer.
Flanagan said that while he could not disclose details of the search warrants, because a judge had ordered them sealed, he confirmed they were looking for documents and computer records.
Murray, a Texas-based cardiologist, allegedly gave Jackson the anesthetic propofol -- commonly known by the brand name Diprivan -- in the 24 hours before he died, the source said. Watch a profile of Murray »
In a statement Monday, the doctor's attorneys said they wouldn't comment on "rumors, innuendo or unnamed sources." In the past, they have said Murray never prescribed or administered anything that could have killed Jackson. Watch CNN's Ted Rowlands report on drug allegation »
Last week, Texas authorities searched Murray's Houston medical office and storage unit, looking for "evidence of the offense of manslaughter," according to court documents.
Among the items removed from Murray's office were a computer; 27 tablets of phentermine, a prescription-strength appetite suppressant; 1 tablet of clonazepam, an anti-anxiety medication; and some Rolodex cards.
From Murray's storage unit, authorities removed two computer hard drives; an "important contact list"; a suspension notice from Houston's Doctor Hospital; notices from the Internal Revenue Service; and a laundry list of medical and hospital documents.
Ed Chernoff, a Houston lawyer hired by Murray soon after Jackson's death, confirmed at the time that Los Angeles police detectives and federal DEA agents used a search warrant to enter Murray's office in northeast Houston on Wednesday morning.
Chernoff said members of Murray's legal team were at the medical office during the search, which he said "was conducted by members of the DEA, two robbery-homicide detectives from the Los Angeles Police Department and Houston Police officers."
Tammy Kidd, a spokeswoman at Chernoff's office, told CNN the search "was absolutely a surprise to us, because we've had open lines of communication this whole time."
Police have interviewed Murray twice since Jackson's death. A third interview was scheduled for July 24, but was postponed after the search warrants were executed. It's unknown when the next interview will take place.
Among those who have indicated that Jackson may have been using dangerous prescription medication are nutritionist Cherilyn Lee, who said Jackson pleaded for the powerful sedative Diprivan despite being told of its harmful effects.
Meanwhile, the Los Angeles County coroner's office continues to investigate the cause of Jackson's death on June 25. It has been waiting on toxicology lab results, but a final autopsy report is expected as soon as this week, a coroner's spokesman has said.