The Los Angeles Times reports Jackson was pronounced dead this afternoon after being taken to UCLA Medical Center by paramedics responding to an emergency call from the performer’s rented mansion in Los Angeles. According to the Times, the 50-year-old performer arrived at the medical center in a coma.

Jackson reportedly suffered a cardiac arrest earlier today and was taken to the medical center shortly after 12:26 p.m. California time. According to TMZ, Jackson was not breathing and attempts by paramedics to resuscitate him failed.

Jackson was only weeks away from what could have been the biggest comeback in show biz history – 50 shows at London’s O2 Arena – beginning July 13 and running through March 6, 2010. Rumors that Jackson was ill and not physically capable of doing the shows emerged when the first shows – originally scheduled for the second week of July – were pushed back to 2010.

Click here for the Los Angeles Times report.

Click here for TMZ’s report.