Michael Jackson’s former security guard, Alberto Alvarez, testified on Thursday, giving details of the frantic afternoon when the "Beat it" singer died.

Alvarez said during the trial of Jackson's doctor that he went to help the legendary singer after his assistant called him on his cell phone. 

Shocked at seeing Jackson lying motionless on his bed, eyes slightly open, Alvarez barely had time to react when he heard the singer's daughter scream "Daddy!" from the doorway. He led her and Prince from the room, trying to comfort them.

Alvarez then said Murray told him to put vials of medicine he scooped from Jackson's nightstand into a bag. Alvarez complied and also placed an IV bag into another bag.

Alvarez's testimony was key for prosecutors who contend Murray, who has pleaded not guilty, was intent on concealing signs that he had been giving the singer doses of propofol as a sleep aid.

Alvarez said he thought Murray might be preparing to take the items to the hospital, but the bags never made it to the hospital and the bodyguard never questioned the doctor.

If convicted, Murray, 58, could face up to four years in prison and lose his medical license.

Defense attorney Ed Chernoff asked whether there was enough time for Alvarez to shield Jackson's children, survey the room and stow away the drugs in the brief period that phone records show he was in the home before calling emergency responders.

The bodyguard insisted there was, telling the attorney, "I'm very efficient, sir."

Chernoff was not convinced, questioning whether 30 seconds was enough time for the dramatic sequence to play out. Alvarez assured him there was.

The defense attorney also challenged Alvarez's recollection, asking whether the collection of the vials happened after paramedics had come and whisked Jackson to a nearby hospital. Alvarez denied it happened after he called 911.

Chernoff questioned why Alvarez didn't tell authorities about Murray's commands to bag up the medication immediately after Jackson died, but instead waited until two months after the singer's death. The bodyguard said he didn't realize its significance until seeing a news report in late June in which he recognized one of the bags detectives were carrying out of Jackson's mansion.

The burly Alvarez became emotional as the 911 call was played for jurors. Jackson's mother, Katherine, appeared distraught and her son, Randy, huddled next to her and put his arm around her.

"Was that difficult to hear?" prosecutor David Walgren asked."It is," Alvarez replied.

Alvarez's testimony allowed Walgren to present jurors directly with a bottle of propofol that they've heard much about throughout the previous two days of the trial.

Jurors intently looked at the bottle, which appeared to still contain some liquid.

Walgren asked whether anything good had happened to Alvarez as a result of his experience in Jackson's bedroom.

"No sir," Alvarez responded.

Media outlets reportedly offered him up to $500,000 for interviews, but Alvarez said he always refused. "It's caused a lot of financial problems," he said, starting to choke up. "I went from a great salary to hardly anything."

Based on reporting by the Associated Press

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