The latest breaking updates, delivered straight to your email inbox.

A young child who fell from a window at an apartment building in Boston's Dorchester neighborhood last week has died, the Suffolk County District Attorney's office said.

Police said first responders were called to 12 American Legion Highway at 3:17 p.m. on Aug. 17 for a call that a 4-year-old boy fell out of a fourth-floor window.

Arriving first responders found the child with serious, life-threatening injuries, and he was rushed to a Boston hospital.

The boy's mother, Erika Moon, said her son, Isaac, somehow got around the baby gate in their apartment and managed to open a window.

"He opened the gate that's blocking my window and he opened the window. He leaned out and 'boom,' he fell out the window," Moon said. "I heard the boom, so I went running down and I picked him up. He wasn't breathing."

M0on said her son had spectrum autism, was non-verbal and had no sense of danger.

Neighbors told WCVB they heard a scream, then ran outside to see the boy motionless on the ground.

“I heard a scream, and in hearing the scream, I looked out the window. That’s when I saw the child,” said Nelson Peguero. “I don't know them, but I saw a woman come out — not sure if it was the child’s mother. She picked up the child and was desperate for help.”

Officials said the investigation was being conducted jointly by the Suffolk County District Attorney's Office, Boston Police Homicide Division, district detectives and the Crimes Against Children Unit.

Hearst Television participates in various affiliate marketing programs, which means we may get paid commissions on editorially chosen products purchased through our links to retailer sites.