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Michael Jackson's personal chef Kai Chase has spoken out about the day King of Pop died. Was Jackson dead for hours before anyone discovered he wasn't breathing? Jackson insider Diane Dimond talks about what may have happened before that 911 call was made at 12:21 p.m. on June 25.

"Police sources are telling me they're trying to figure out whether Michael Jackson was already dead when paramedics arrived," Dimond tells ET. "And now the inside account from chef Kai Chase is an important part of the timeline for police. Chase is now publicly saying that she first noticed something was wrong that morning when Dr. Conrad Murray broke routine ... and didn't come downstairs first thing to get Michael's granola and juices."

In Chase's new interview with the Associated Press, she paints a timeline of Michael's final hours, saying that around 9 or 9:30 p.m., Dr. Conrad Murray usually arrived and would go upstairs to Jackson's bedroom. Kai told the AP that at 12:05 p.m., Dr. Murray called the family for help, asking for Michael's son Prince.

"Early that morning -- a full three hours before anyone called 911 -- Dr. Murray is reported to have called his Houston office," Diane says. "Two staffers there were dispatched to Murray's storage site where they removed boxes. What exactly was in those boxes? No one's saying."