CLERMONT, Fla. -

A Lake County school bus driver failed to drop off a 4-year-old autistic student for 3 hours, according to his family, who says they had no idea where their son was, or if he had even boarded the bus at all.

Chancellor Barclay is unable to express his thoughts verbally, according to his parents. That's why the autistic student is enrolled in ESE classes at Groveland Elementary, where he receives speech and language therapy. It is also why his parents say they usually try to exchange emergency contact information with the school bus drivers who transport Chancellor between school and the Clermont music store where his father works.

But when classes resumed August 20, Chancellor's mother says she had not yet met her son's afternoon bus driver. Still, she felt she had adequately communicated her son's travel arrangements with school officials.

"I was out here waiting by 3:10," said Chris Ann Barclay, who wanted to make sure her son got off his school bus after his first day of class.

But by 3:45 p.m. the bus still had not arrived. Concerned about her son's well-being, Barclay said she tried contacting school officials. "I started calling the school. Got a busy signal," said Barclay. "I called a number I had for the bus department. Got a busy signal."

A short time later, Barclay said she finally reached somebody, but said that person was unable to make contact with her son's school bus driver. "She actually had me on the line while she was calling on the radio, and nobody was answering," said Barclay.

By 5:00 p.m., two hours after class had been dismissed, Barclay said she became very upset, in part because she knew her autistic son would be unable to explain to the bus driver where he needed to go.

"We finally decided to call the police," said the child's father, Ricardo Barclay.

About that same time school officials reportedly located the bus, according to the family. But it would be nearly another hour before they say the 4-year-old was dropped off.

"He got off the bus. He was hysterically crying," said the mother.

The family said their son complained of groin pain, which they believe was likely caused by his inability to use a restroom during the 3-hour trip home. However, to ensure that their son was treated well, the family is asking school officials to show them surveillance videos taken on board the bus.

A Lake County school spokesman said the incident is under investigation. Both the bus driver and the bus monitor were substitutes who were filling in on the very first day of school, according to district officials.