CHICAGO (AP) — Chicago Public Schools have been hit with a lawsuit alleging a teacher allowed a 9-year-old student to be beaten in a school bathroom by her friend.

The lawsuit filed in U.S. District Court by Asia Gaines claims her son suffered bruises all over his body as a result of the September beating with a belt.

Attorney Al Hofeld Jr. indicated the reason the fourth-grader at George W. Tilton Elementary School was punished wasn’t completely known.

The lawsuit claims teacher Kristen Haynes and Juanita Tyler dragged the boy into a bathroom, where Tyler beat the boy as Haynes returned to her classroom. Hofeld said Tyler is a distant relative of the boy, who the boy didn’t know.

CPS said Haynes no longer teaches at the school.

Tyler and Haynes have been charged with battery. It wasn’t immediately known if either have legal representation.