ANAHEIM – Anaheim Union High School District is investigating how an autistic 15-year-old student was left inside a school bus for about six hours.

The Savanna High student, who is unable to speak and has seizures, sat inside the vehicle parked at the district bus yard for most of the school day, said the teen’s mother.

The incident occurred Sept. 11. Temperatures that day hit the mid-80s. The student, Patrick Hoang, appeared physically fine when he returned home that day, mother Lucie Hoang-Ngo said. But she worries her son may have been frightened or suffered other emotional harm from being left alone.

“I just don’t know how something like this could have happened,” Hoang-Ngo said. “I am angry because no one is giving us any answers.”

Hoang-Ngo said she’s asked for several weeks to meet with district administrators, hoping for a detailed explanation of what went wrong that day. But officials have provided very little information, she said.

Anaheim Union operates its own transportation services and employs the drivers. District policy requires bus drivers to go through vehicles after students are dropped off to ensure no students remain inside. The district has not disclosed the name of the driver involved in this incident or whether the person has been disciplined.

Anaheim Union spokeswoman Pat Karlak said she could not provide details regarding the ongoing investigation. She said the fact that the investigation has lasted nearly two months is not unusual for cases involving personnel matters or potential student safety issues.

“We understand that parents would like to have immediate answers, but sometimes investigations take more time than parents may anticipate,” she said. “When the investigation is completed, we will meet with the parent and/or provide an outcome of the investigation.”

Since kindergarten, Hoang has ridden a bus designated for special education students, with about 15 to 20 other children.

About 7:20 a.m. Sept. 11, the bus picked up the student in front of the family home, his mother said. The parents then received a call around 2 p.m. saying they needed to pick up their son from the district office. Staff told the parents that Hoang had been alone inside the school bus all day.

“I could not believe what they were telling me,” the mother said. “I kept asking them how something like this could happen.”

A school nurse examined Hoang and his parents took him to his doctor afterward as a precaution.

Karlak said there is no timetable for the conclusion of the district’s investigation.

Hoang-Ngo said officials have since offered to have an instructional aide ride the bus with her son. But the mother said she no longer trusts the district transportation system.

She now drives her son to school every day.

Reports of disabled students left in school buses are uncommon, although a handful of incidents are reported nationally each year. In Orange Unified, a driver was fired in 2001 after leaving a disabled student in a bus for seven hours.

Contact the writer: 714-796-2258 or fleal@ocregister.com