The brother of the Illinois lottery winner murdered last year says he’s the one who raised questions about the mysterious death.

Urooj Khan won $1 million in the lottery in May, and was killed in July.

His brother, Imtiaz Khan, tells the Chicago Tribune about a week after his brother’s unexpected death, Imtiaz Khan asked the medical examiner’s office to take another look at the case.

Additional testing eventually discovered his brother died of cyanide poisoning.

Khan and his sister are currently in a court battle with his brother’s widow over his estate, which includes the lottery winnings and dry cleaning business.

Kahn’s widow, Shabana, and her father were questioned about her husband’s death.  Both have denied any involvement in the homicide and have not been accused of a crime.

Imtiaz Khan says he wants to make sure Khan’s daughter from a previous marriage receives her share of her father’s estate.