The speculation will continue, but this is what we know so far.
No official cause of death will be announced until after an autopsy is performed, but doctors have indicated that Michael Jackson indeed died after suffering cardiac arrest this afternoon.
"My brother, the legendary King of Pop, Michael Jackson, passed away on Thursday, June 25, at 2:26 p.m." brother Jermaine Jackson told the media gathered outside Ronald Reagan UCLA Medical Center shortly before 6:30 p.m.
"It is believed he suffered cardiac arrest in his home. However, the cause of his death is unknown until the results of the autopsy are known."
Jackson had been renting a home in Los Angeles' upscale Holmby Hills neighborhood.
Los Angeles Police tell E! News that its "standard procedure" investigation into the circumstances of Jackson's death is ongoing.
Jermaine continued: "The personal physician who was with him at the time attempted to resuscitate my brother. As did paramedics who transported him" to the hospital.
"Upon arriving at the hospital at approximately 1:14 p.m., a team of doctors, including emergency phsyicians and cardiologists, attempted to resuscitate him for a period of one hour and they were unsuccessful.
"Our family requests that the media please respect our privacy during this tough time, and may Allah be with you Michael, always."
Jackson's body was transported tonight by helicopter from UCLA to USC Medical Center downtown, and then taken by van to the coroner's office, where an autopsy is expected to be performed as soon as Friday.
L.A. County Department of Coroner spokesman Craig Harvey said that the full extent of the coroner's findings will not be available for several weeks, when the results of toxicology tests come back.
Because Jackson was not under the care of any UCLA doctor for a particular condition at the time of his death, the job of signing off on his death certificate goes to the coroner's office.
(Originally published June 25, 2009, at 6:22 p.m. PT)