An Illinois police officer is reportedly under investigation after he allegedly pulled over a school bus to deliver lunch to his son.

A driver with Durham Bus Service filed a complaint last week with the Johnsburg Police Department alleging Lt. Brian Keller used his unmarked black Dodge Charger to stop the bus in McHenry County to deliver lunch to his son on board, the Chicago Tribune reports.

The bus, which was located outside of Keller’s jurisdiction when he stopped the vehicle, was en route to Marion Central Catholic High School in Woodstock, roughly nine miles from where the incident occurred on Nov. 11.

School officials referred inquiries to the bus service. A spokeswoman for Durham Bus Service would only confirm that the bus was transporting high school students at the time.

Keller and the bus driver were unreachable for comment, the newspaper reports. Keller was identified in a report of the incident filed in McHenry County.

“The apparent purpose of the stop was to issue his son his lunch for the day,” the complaint read, according to the Tribune.  “The complainant was advised that documentation would be made, however, she needed to contact (the Lake County Sheriff’s Office) regarding the incident.”

Lake County Undersheriff Raymond Rose acknowledged the complaint, which he said was currently under investigation.

“We received information regarding allegations of inappropriate actions by Lt. Brian Keller,” Rose told the news site in a written statement. “As a result of that, Sheriff (Mark) Curran and I have ordered an internal investigation into the allegations.”

Keller reportedly worked closely with the department’s chief until he recent transfer to a new position at a local court.