Spc. Taylor Hotzoglou, 22, an Afghanistan War veteran, was shot to death April 29, Clarksville police said.
Officers responding to a report of a car crash about 12:30 a.m. discovered the soldier's body inside a gray 2009 Subaru Impreza.
Police initially reported that Hotzoglou was last seen giving two men a ride, according to news accounts. On Thursday, two teenagers were arrested in connection with the slaying.
Giovanni Johnson, 18, is being held without bond at the Montgomery County Jail, and a 17-year-old is currently in juvenile detention, police said.
Hotzoglou's apparent act of kindness isn't surprising, friends and fellow soldiers said Saturday.
"He had a really big heart," said Mike Opulskas, a soldier who served with Hotzoglou in Afghanistan from August 2010 to August 2011. "He'd give you his last 10 cents if you needed it."
Hotzoglou had been stationed at Fort Campbell, an Army base north of Clarksville, Opulskas said.
Weeks before his death, Hotzoglou gave a homeless person a ride, buying him a meal along the way, said Lethia Van Luven, who lived near Hotzoglou in Clarksville.
Van Luven said she scolded her friend for taking a risk by picking up a stranger.
"Taylor was like, 'But what if it was me? I'd want somebody to be kind enough and trusting enough,' " she said. "It's unfathomable to me that it was someone so trusting and so giving that lost his life."
Hotzoglou graduated from Rocky Point Junior-Senior High School in 2007, according to his Facebook page.
"The kids just loved him. He was a great role model," she said.
Scott Martin, a soldier also stationed at Fort Campbell, said he lost his best friend.
"He loved the Army . . . he loved his country," Martin said.
Hotzoglou was an infantry soldier in Whiskey Company, part of the 101st Airborne Division's 4th Brigade Combat Team, according to Martin.
He said it's hard to deal with the fact his friend was killed, not in battle, but on American soil.
"It's unthinkable," he said.
Visitation will be Sunday from 2 to 4 p.m. and 7 to 9 p.m. at O.B. Davis Funeral Homes in Miller Place.
Services will be held at 11 a.m. Monday at the funeral home. Burial will follow at Sea View Cemetery in Mount Sinai.