The U.S. Department of Education said on Tuesday it is investigating the Denver schools system for allegedly discriminating against women and girls by converting a female bathroom to all-gender.

The U.S. Education Department said it is investigating Denver Public Schools for alleged discrimination after the district converted a girl’s restroom on the second floor of East High School into an all-gender restroom while leaving the other bathroom exclusively for male students.

The U.S. Department of Education’s Office for Civil Rights will open an investigation into Denver Public Schools for “discriminating against its female students” by creating an all-gender bathroom at East High School,