Dietrich school employees gathered key evidence in a grisly sexual assault case involving a high school student, interviewing witnesses before notifying police, the Associated Press reported Wednesday.

Based on a review of nearly 2,000 pages of documents from Attorney General Lawrence Wasden’s office, the AP’s Rebecca Boone described the school’s response to the October 2015 attack in a high school locker room. Three white football players were ultimately charged with attacking a black, mentally disabled teammate.

According to Boone’s report, Dietrich Superintendent Ben Hardcastle gathered key evidence, including a coat hanger believed to be used in the assault. Hardcastle interviewed the suspects and some of the 27 potential witnesses to the attack, and waited four days before notifying the sheriff’s department, Boone reported.

Hardcastle declined comment to the AP.

Boone’s report also chronicled a culture of locker-room bullying leading up to the attack, and said the victim was pressured about testifying about the attack.

Three students were charged with sodomy in the case. John R.K. Howard was sentenced last week to probation and community service on a reduced charge of felony injury to a child. The other two cases are pending in juvenile court, and the records are sealed.

The victim’s parents have filed a $10 million civil lawsuit against the Dietrich district, saying school officials knew about a pattern of escalating bullying and violence, or should have known about the incidents.