On June 25, 2009, Jackson died while in his bed at his rented mansion at 100 North Carolwood Drive in the Holmby Hills district of Los Angeles. His life was cut shockingly — and so far, mysteriously — short.

The 50-year-old musical superstar died Thursday, just as he was preparing for what would be a series of 50 concerts starting July 13 at London’s famed 02 arena. Jackson had been spending hours and hours toiling with a team of dancers for a performance he and his fans hoped would restore his tarnished legacy to its proper place in pop.

An autopsy was planned for Friday, though results were not likely to be final until toxicology tests could be completed, a process that could take several days and sometimes weeks. However, if a cause can be determined by the autopsy, they will announce the results, said Los Angeles County Coroner Investigator Jerry McKibben.

Jackson died at UCLA Medical Center after being stricken at his rented home in the posh Los Angeles neighborhood of Holmby Hills. Paramedics tried to resuscitate him at his home for nearly three-quarters of an hour, then rushed him to the hospital where doctors continued to work on him.

“It is believed he suffered cardiac arrest in his home. However, the cause of his death is unknown until results of the autopsy are known,” his brother Jermaine said.

Cardiac arrest is an abnormal heart rhythm that stops the heart from pumping blood to the body. It can occur after a heart attack or be caused by other heart problems.