INDIANAPOLIS (AP) — A teenage shoplifting suspect who died in Indianapolis police custody was forced to lie on his back for nearly 40 minutes after he was cuffed with his hands behind him, leaving the overweight, exhausted teen in distress and unable to breathe properly, the attorney for his family said Thursday.

Terrell Day, 18, died Saturday in police custody after he had complained of breathing problems. The Marion County coroner ruled Monday that the black youth died of a heart attack.

Indianapolis police said officers were called Saturday to a clothing store on the city’s far east side after a gun-wielding man who had allegedly shoplifted fled the business. Police said they found Day near a handgun in a grassy area behind a nearby gas station.

Day family attorney Nathaniel Lee said the teen ran more than 400 yards and was exhausted when officers found him. He called the way the youth was handled by officers “tantamount to a form of torture.”

Lee said police handcuffed the 5-foot-6 high school senior who weighed more than 250 pounds behind his back, placed Day on his back and kept him in that position even as he struggled to breathe.

“This is an 18-year-old who died, I think, unnecessarily,” he said during a Thursday news conference with Day’s mother and other relatives.

Indianapolis’ Public Safety Department said Monday that a responding EMS crew determined Day was fine to be taken into custody and a responding ambulance then left the scene. The department said Day signed a release stating he did not require additional medical attention.

But Lee said an EMS report he had obtained shows an officer actually signed that form instead of Day.

When a jail wagon arrived, police said Day again complained of breathing problems. A second ambulance arrived as Day’s condition worsened. Despite the second medical crew’s efforts, he died in the back of the ambulance, authorities said.

During Thursday’s news conference, Lee showed a video taken by a bystander that shows Day handcuffed on his back while officers stand over him, talking. At one point, Day tried to roll over onto his side to get more air into his lungs, Lee said, but the officers rolled him back onto his back.

The footage shows officers helping Day onto his feet at one point, but the teen’s legs were wobbly, his body unsteady and Day’s head eventually falls forward as if he were passing out.

Officers then return Day to the ground after he’s unable to stand, the footage shows.

Lee said he suspects a final autopsy report still weeks from completion will show that Day died from asphyxiation and multiple heart attacks because he couldn’t breathe properly while on his back.

“Your hands are behind your back and you’re overweight — this is basically tantamount to a form of torture because you can’t breathe,” he said.

Lee said he’s still investigating Day’s death and hasn’t decided if the family might sue over the teen’s death.

He sent a letter Friday to Indianapolis Police Chief Rick Hite stating that “suspects should not be forced to lie down on the ground after severe physical exertion.” The letter asks Hite to review “and correct this department policy and procedure immediately.”

Police spokesman Lt. Rick Riddle declined to comment on Lee’s assertions, citing the department’s ongoing investigation of Day’s death. “We need to reserve comment until the investigation concludes,” he said.

Day’s mother said her son had no known history of heart defects or serious medical issues.

Shanika Day, a mother of four other children, said her son “was a happy child” who worked a part-time job at a fast-food restaurant and was a senior at Warren Central High School. She said she can’t fathom the manner in which he died.

“If they just would have saved his life, got him the help he needed — he needed help. And for me to just see my child laying out there on the ground and everybody just standing around and not helping …,” she said, her voice trailing off.

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