A 19-year-old man with special needs who died Friday after he was found unresponsive on a school bus in Whittier has been identified.
Hun-Joon Lee was identified as the victim Saturday by the Los Angeles County Coroner's Department.
Firefighters at 4:15 p.m. received a call of a person not breathing at 9402 Greenleaf Avenue in a Whittier school distrcit parking lot, according to a Los Angeles County Fire Department dispatcher.
Responding officers saw several bus drivers performing CPR on a man, said Whittier police officer Brad White.
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They took over the resuscitation effort, but were unable to revive the victim, White said.
The search for the student started on bus #243 after Lee's mother reported her he never made it home from school, authorities said.
"That's when the bus driver walked to the bus yard behind me [and] discovered the student lying in the aisle way near the front of the bus unresponsive," White said.
The bus driver was held for questioning but was released, the officer said.
The investigation is ongoing.
Pupil Transportation Cooperative, the private bus company, which contracts with the schools issued a statement of sympathy but didn't say whether its bus drivers are required to conduct "head counts" of special needs students.
The yard is west of Sierra Vista High School and the Whittier Adult School, where the man was a student, White said.
Coroner's personnel arrived at the scene Friday and said they would determine the cause of death once proper notifications have been made, White said.
"Nobody wants to be responsible for something like this, you know?" said Tim McDermott, a witness.
City News Service contributed to this report.