LOS ANGELES (AP) — The promoters of Michael Jackson's ill-fated comeback concerts watched the singer waste away and should have reached out to his family for help, the superstar's mother tearfully told a jury on Monday.

Katherine Jackson said she didn't know the extent of her son's weakness until after the start of her trial against AEG Live LLC.

"They watched him waste away," she said after her attorney cited several emails from top workers preparing for the "This Is It" shows. The messages described her son's condition as deteriorating and cited his inability to rehearse.

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"They could have called me," Katherine Jackson, 83, said.

She claims AEG Live failed to properly investigate Dr. Conrad Murray, who was later convicted of involuntary manslaughter for giving the singer an overdose of the anesthetic propofol.

AEG Live denies it hired the doctor or bears any responsibility for Jackson's death.

Katherine Jackson said she believes AEG Live hired Murray, not her son. She said she never heard of the cardiologist until her son died and indicated that she felt Murray bore responsibility for her son's death.

"Even though he asked for it, he could have said no," she said of Murray.

When asked about conversations she had with her son about prescription drug use, she said she asked him about it when he lived in Las Vegas and he denied he was abusing prescription medications.

"I'm a mother, quite naturally he denied it," she said. "He wouldn't want me to think that."

She said she was aware her son took medications for pain in his back and scalp after he sustained injuries over his career. She said she never saw signs that her son was abusing medications, including when she and several of her children went to the singer's Neverland Ranch in 2002 for an intervention.

Her son was fine but upset that they thought he had a problem, she said.