Michael Jackson's make-up artist warned in the 1990s that the star could die due to his drug addiction, she testified Friday, adding that people were initially lying after his 2009 death.

Karen Faye, who worked for the self-styled King of Pop for 27 years, said she voiced concern to a drugs therapist after Jackson's "Dangerous" tour in the early 1990s, which was cut short when the singer went into rehab.

She was speaking at a Los Angeles trial pitting Jackson's 82-year-old mother Katherine against AEG Live, the promoter of his final tour whom she accuses of negligently hiring doctor Conrad Murray.

Murray was convicted of involuntary manslaughter in 2011. The Jackson family matriarch says AEG Live were responsible for hiring the medic, and should have known he was inappropriate for the job.

Jackson died on June 25, 2009 of an overdose of the anesthetic propofol, given to him by Murray to help with his insomnia. Lawyers for AEG say he had used the drug, usually only meant for a hospital setting, for years.

"Everybody was lying after he died .. and everyone knew," said Faye, who was asked to do the make-up on Jackson's corpse. "I felt retouching Michael was part of that lie and I didnt want to be part of it," she said.

Faye, who also did Jackson's hair, said she began to be seriously worried during the "Dangerous" tour. "I said I was afraid Michael could die," she said, adding: "There were times when he was OK and times when I was worried."

On one tour stop in Singapore she stumbled into his dressing room to find him taking medication, which he said was to reduce a bald spot on his scalp from burns received during an accident while making a Pepsi advert in 1984.

At times on the tour she saw Debbie Rowe, who at the time was a nurse for Jackson's dermatologist Dr Arnold Klein but would later marry the singer, carrying medications for the star.

Faye added that she voiced concerns about Jackson's drug abuse with his siblings Rebbie, LaToya and Randy. The family tried unsuccessfully to get him into rehab in later years, she said.

"I never knew them to be successful ...I'm sure they were trying to help him in any way the could," she said.

The trial continues into its third week Monday.