(CHICAGO) -- The body of a $1 million lottery jackpot winner will likely be exhumed from Rosehill Cemetery in Chicago, according to the Cook County medical examiner, who determined that the winner died of cyanide poisoning.
Last June Urooj Khan, 46, won $1 million in a scratch-off lottery game, or $425,000 after taxes, but he died unexpectedly on July 20. Since there were no signs of foul play or any cause for suspicion, his death was attributed to arteriosclerotic cardiovascular disease, which covers heart attacks, stroke or ruptured aneurysm.
But a few days after the death certificate was issued, a family member called the medical examiner's office and asked that the death be investigated, said Dr. Stephen Cina, Cook County's chief medical examiner. Cina said he could not disclose the identity of the family member because of the ongoing investigation.
"We are in discussion with the state attorney about whether we are going to do an exhumation. Right now, we are leaning in that direction. We have a cause and matter of death on the books, and we're comfortable with that," Cina told ABC News. "If or when this goes to court, it would be nice to have all the data possible."
Cina said the final toxicology results came back in late November showing a lethal level of cyanide, which led to the homicide investigation. Melissa Stratton, a spokeswoman for the Chicago Police Department, confirmed a murder investigation had been "under way," and that the police department had been working closely with the medical examiner's office.
Khan is survived by his wife, Shabana Ansari, 32, and teenage daughter. The family owned three dry-cleaning businesses in Chicago.
Ansari told the Chicago Tribune that Khan was "the best husband on the entire planet" and "extraordinary, nice, kind and lovable."
Ansari could not be reached by ABC News for comment.
The police are not confirming whether Khan's lottery winnings played a part in the homicide.
When asked why cyanide, a chemical asphyxiant that binds to red blood cells and prevents the entry of oxygen, was not found in the initial examination of Khan's body, Cina said, "Quite frankly, it's unusual as a cause of death, so it's not at the top of your mind."
He said about 50 percent of people can smell cyanide, but it is more noticeable when the body is opened up.
Sometimes the coloring of blood changes with cyanide poisoning after death, becoming "more reddish than purple," he said.
"In this case that wasn't particularly striking," Cina said, describing the first examination of Khan's body.
"It strangles your red blood cells at a biochemical level," he said.
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