MONTEREY, Calif. — A student with autism was left on a school bus for up to two hours recently during a heat wave after the bus driver reportedly failed to perform a child check, KSBW reports.

The family of the 11-year-old girl, Bella, told the news source that she was left alone on the bus for two hours. Marci McFadden, a spokeswoman for Monterey Peninsula Unified School District, told KSBW that Bella was left on the bus for 35 minutes.

Bella was picked up on June 19 by a bus that had a special-education aide on board to supervise students with special needs, McFadden told the news source. The weather that day was hotter than usual during that week’s heat wave, according to KSBW. Two hours after Bella left her home, her parents received a phone call from a school staff member stating that she hadn’t shown up at school, Bella’s grandmother told the news source. McFadden also told the news source that the bus driver failed to perform a mandatory child check after completing the route. (The aide was busy helping another student when the bus arrived at the school, and is not suspected of wrongdoing.) Bella was found uninjured in the back of the bus in the bus yard, according to KSBW.

The bus driver, who has worked for the district for five years, has been placed on administrative leave and will be investigated further before facing any punitive actions, the news source reports. PK Diffenbaugh, the district’s superintendent, wrote in a letter to Bella’s family that the district would follow up with its internal discipline process, including “pursuing a dismissal” for those responsible after the investigation is finished, retrain drivers on procedures to make sure all students exit the bus safely, and look into “a technology system that will further safeguard against such instances,” according to the news source.

The incident follows one that occurred in the state in 2015 in which a 19-year-old with autism, Paul Lee, died after being left on a school bus for several hours on an extremely hot day. Lee’s family recently reached a $23.5 million settlement with the school bus company. Another outcome was the passage of the “Paul Lee School Bus Safety Law,” which requires all school buses in California to be equipped with child-check reminder systems by the start of the 2018-19 school year.