Jackson appeared to have suffered a heart attack, another person with knowledge of the situation who was not authorized to speak publicly and requested anonymity. A heart attack is a blocking of the arteries that deprives the heart of adequate blood and can cause cardiac arrest.

Jackson's brother Jermaine has said it was believed the pop singer went into cardiac arrest, an interruption of the normal heartbeat that can be caused by factors other than a heart attack.

The coroner's office said there were no signs of foul play or trauma.

Phillips said AEG Live held multiple insurance policies covering cancellation of the shows, and that some time in February Jackson submitted to several hours of physicals that the insurance underwriter insisted upon, and that Jackson passed them all.

"We had pretty good coverage, but a lot of it is going to depend on the toxicology results," he said. "We need to know what the cause of death was."

——— AP Writers Sophia Tareen in Chicago, Gillian Flaccus, Beth Harris and Mike Blood and AP Global Media Services Production Manager Nico Maounis in Los Angeles and Shawn Pogatchnik in London contributed to this report.