(PHOENIX) -- Arizona authorities have obtained a canister labeled "cyanide" from the car of a businessman who apparently poisoned himself in a courtroom after he was found guilty of arson. Still, a cause of death has yet to be determined.
The Maricopa County Medical Examiner's Office is awaiting toxicology results to determine what, if any, substances Michael Marin ingested moments after a jury convicted him of burning down his Phoenix mansion.
"The body tells us the story," medical examiner spokeswoman Cari Gerchick said today. "We reserve any kind of determination of cause and manner until everything is complete."
Marin, 53, was convicted June 28 of purposefully burning down his $2.55 million mansion in the tiny Biltmore Estates neighborhood of Phoenix after he was unable to keep up with mortgage payments and a plan to raffle his house through a charity fundraiser failed. He faced up to 16 years in prison.
Maricopa County Sheriff Joe Arpaio Tuesday said Marin's son received a delayed email hours after his trial, informing him of how to handle his affairs if things went poorly in court and where to find his car.
Arpaio said at a news conference that records indicated Marin purchased the cyanide powder in 2011 before the start of his trial. He speculated the convicted arsonist made capsules he could swallow in the courtroom from the cyanide powder.
"I don't know what his motive was to go public and allow the whole world to see," Arpaio said at the news conference, ABC affiliate KNXV reported. "He committed suicide in front of the cameras in the courtroom for the whole world to see."
Cameras captured Marin's descent toward death. Moments after the verdict was read, a seemingly distraught Marin buried his face in his hands and appeared to place something in his mouth.
His face began to turn red. Minutes later, he took a sip of a liquid from a plastic sports bottle, turned to get a tissue, experienced convulsions and collapsed.
He was pronounced dead at the hospital, said Jeff Sprong, spokesman for the Maricopa County Sheriff's Office, which is investigating the death.
Marin, who amassed his fortune working in finance and as a Yale-educated lawyer, set fire to his 6,600-square-foot mansion July 5, 2009, after he was unable to make a $2.3 million payment on his balloon mortgage the following month.
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