Katherine Jackson concluded her tearful testimony at the on-going trial against the promoters of Michael Jackson's ill-fated comeback concerts, claiming AEG Live watched as the King of Pop "wasted away" before his untimely death.

Hanging her head and welling up, Katherine Jackson said she didn't know the true extent of her son's weakness until after the start of her family's trial against AEG Live, reports Billboard.

"They watched him waste away," she said after her attorney had cited emails from workers preparing for the "This Is It" shows in London. The messages described Michael Jackson's condition as deteriorating and confirmed that he was unable to rehearse. 

"They could have called me," said Katherine, "He was asking me for his father. My grandson told me that his daddy was nervous and scared."

Earlier, Katherine had faced intense questioning from a bullish attorney working for AEG Live, who asked the family matriarch why she hadn't read through thousands of pages of testimony of asked her grandchildren what happened to her father, if she wanted to file a lawsuit to find out the truth about her son's death.

Katherine maintains that AEG Live failed to investigate the credentials of Dr Conrad Murray, who was later convicted of the involuntary manslaughter of Jackson following a lethal overdose of the anaesthetic propofol.

AEG Live denies that it hired Dr Murray, or bears any responsibility for his death.

Jackson's mother said she was aware her son took medications for pains in his back, though said she never saw signs that her son was abusing his prescriptions. 

Michael JacksonMichael Jackson At The Press Conference For 'This Is It'

Katherine Jackson
Katherine Jackson Gave Teary Testimony in Court