Police in California are investigating the death of a 19-year-old special needs student.
A transportation company picked the man up on Friday morning to bring him to an adult school.
When the student did not arrive home at around 4 p.m., his mother called the school and the school contacted the bus company to report him missing.
A bus driver discovered the student lying in the aisle of the bus. The driver and officers tried to revive the student but he was later pronounced dead.
Police have interviewed the bus driver but released him.
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