Thaddeus Farrow shot himself in the torso, the spokesman said after an autopsy was performed Thursday.
Farrow was found inside his car at about 12:45 p.m. Wednesday in Roxbury "suffering from a life-threatening injury," according to a statement from Connecticut State Police Trooper Kelly Grant.
He was transported to Danbury Hospital, where he was pronounced dead at 2:30 p.m. Wednesday. He lived in Torrington.
Mia Farrow posted a statement on Twitter about her adopted son's death.
"We're devastated by the loss of Thaddeus, our beloved son and brother. He was a wonderful, courageous person who overcame so much hardship in his short life. We miss him. Thank you for the outpouring of condolences and words of kindness. If you or someone you love needs help, or if you want to support a group doing life saving work, please visit https://afsp.org/," the Twitter post says.
The link goes to the American Foundation for Suicide Prevention.
State police were investigating the incident in which Thaddeus Wilk Farrow's car was found on Route 67 just north of Carriage Lane in Roxbury. There was "no criminal aspect" to the incident, state police said.
Mia Farrow has a home in nearby Bridgewater.
Thaddeus Wilk Farrow, who was adopted from India, was a paraplegic due to polio. He was one of Farrow's 14 children, 10 of whom were adopted. Three have died. His brother Ronan Farrow is a journalist for NBC News.
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