The Maricopa County medical examiner’s office toxicology tests showed that Michael Marin had the poison in his system.

After he was found guilty of arson in June, Marin put his head in his hands and appeared to put something in his mouth. He then drank from a sports bottle.

It was a bizarre ending to a case that began in 2009 when he emerged from his burning Phoenix-area mansion in scuba gear.

Prosecutors said he torched his home when he couldn’t keep up with the payments. Marin faced seven to 21 years in prison.

Marin had summited Everest and wrote on his Facebook page that he had scaled six of the world’s seven tallest mountains. He also was an art collector who had original Picassos.

Prosecutors painted him as a desperate man who had $50 in his bank account in July 2009, down from $900,000 a year earlier. He also had a monthly mortgage payment on the mansion of $17,250 and an upcoming balloon payment of $2.3 million.

Marin also owed $2,500 a month on a different home and owed $34,000 in taxes, prosecutors said.

On July 5, 2009, Marin told investigators that he escaped a blaze in his 10,000-square-foot mansion using a rope ladder and wearing scuba gear to avoid inhaling smoke.

Fire investigators later determined that the blaze was intentionally set.