Updated 4:46 p.m. EST
A law enforcement official says prosecutors plan to charge Michael Jackson's doctor with manslaughter.
The official told The Associated Press on Tuesday that prosecutors will file a criminal complaint against Dr. Conrad Murray in court rather than go through a secret grand jury.
The person is not authorized to speak publicly about the case and only spoke on condition of anonymity.
The complaint would be the prelude to a public hearing in which a judge would weigh testimony from witnesses to decide if there is cause to try him on an involuntary manslaughter charge.
Murray arrived in Los Angeles Tuesday in anticipation of a decision from the district attorney's office on possible charges, a spokeswoman said Tuesday.
, who practices in Houston, arrived in Los Angeles last weekend and one of his lawyers, Edward Chernoff, plans to join him, spokeswoman Miranda Sevcik said.
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"Dr. Murray is in Los Angeles for a dual purpose - on family business and to be available for law enforcement," Sevcik said. "We're trying to be as cooperative as we can."
There is still no official word on when an announcement about any charges might come. David Walgren, the deputy Los Angeles County district attorney handling the case, declined to comment Tuesday.
The district attorney's office has for weeks been working closely with Los Angeles Police Department investigators to build a case against Murray. Two law enforcement officials have told the AP that Murray is in Jackson's June 25 death from an anesthetic overdose.
The officials spoke only on condition of anonymity because they are not authorized to speak publicly about the case.
Jackson, 50, hired Murray to be his personal physician as he prepared for a strenuous series of comeback performances in London. He died in Los Angeles after Murray administered the powerful general anesthetic propofol and two other sedatives to get the chronic insomniac to sleep, according to the Los Angeles County coroner's office, which ruled the death a homicide.
Murray has denied any criminal wrongdoing.
"We continue to maintain that Dr. Murray neither prescribed nor administered anything that should have killed Michael Jackson," Sevcik said.
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