CASCO — The Cumberland County Sheriff’s Office is investigating a reported assault on a school bus in Casco.

Capt. Don Goulet said a 16-year-old boy allegedly assaulted a 13-year-old boy Thursday on the way home from school.

The younger boy’s mother took her son to a hospital and notified police.

The exact nature of his injuries was not disclosed.

Goulet told WMTW-TV that the allegation is under investigation but there have been no arrests.

Casco is part of the school district that also includes Bridgton, Naples and Sebago.

School officials could not be reached.