A 17-year-old boy with Down syndrome and autism fell to his death down a garbage chute in a high-rise Chicago apartment building . Police discovered the body of Charlie Manley inside the building's trash compacter.

He apparently climbed into the trash chute and fell 46 floors to his death Monday night, according to police. Residents say the chutes are about four feet off the ground and covered with a metal door.

Police say the boy's parents were awakened by an alarm in their apartment-set off when the boy left-but then could not find him during a frantic search.

Neighbors described the teenager as a friendly, upbeat boy who was well known in the building located in Chicago's Gold Coast neighborhood just north of downtown. "He was always out, talking to everybody in the building," said Carolyn Licata, a building resident.

Neighbor Barbara Georgans wondered how he was able to climb into such a small opening, estimated at less than two square feet. "Maybe they should have had some kind of a shield to prevent something like that."

The Chicago medical examiner's officer conducted an autopsy on the boy and ruled his death an accident.

The boy's father, John Manley, is a Chicago hedge fund investor who has supported the Special Olympics over many years.