(CNN) -- A U.S. Army soldier who lost both legs serving in Iraq fell to his death from a roller coaster in upstate New York, police said.
James Hackemer, 29, was riding the Ride of Steel roller coaster at Darien Lake Theme Park Resort on Friday when he plummeted some 200 feet to the ground, according to Sgt. Greg Walker of the Genesee County Sheriff's Office.
"They were descending from one of the hills when he became dislodged from the roller coaster and fell to the ground," Walker said.
Hackemer, who had been fitted with prosthetic legs, was not wearing them on the ride, according to senior dispatcher James Tripp of the Sheriff's Office.
Hackemer, a sergeant, had spent three years in rehabilitation after he lost both legs in an improvised explosive device blast in Iraq in 2008, according to CNN affiliate WVIB.
This was his first trip to the park since returning to his home in Gowanda, New York, in March, WVIB reported.
"However long he was on that ride, (it) had to have been the best time in the last 3 1/2 years," his sister Jody Hackemer told WVIB.
"It was the only time (that he) felt completely normal again," she said.
The park is working closely with local and state authorities to investigate the death.
"We are all brokenhearted by this tragic accident and will continue our support of both the family and the investigation," park spokesman Chris Thorpe said in a press statement.