*No charges will be filed after an incident at Texas A&M University in which black high school students on a campus tour reported being subjected to racial slurs and taunts, the university said Wednesday.

University police said in a statement that they closed their investigation into the Feb. 9 incident after interviewing several witnesses, including the high school students and teachers on the tour, reports the AP.

One Texas A&M student allegedly approached two of the high school students and told them to check out her Confederate flag earrings. According to police reports released Wednesday, other A&M students shouted, “Go back where you came from,” and used a slur.

But several Texas A&M students denied using or hearing the slur, or shouting anything at the tour group other than, “Howdy,” a common greeting on campus. One student acknowledged heckling a high school student about wearing a University of Texas backpack — a reference to A&M’s biggest rival.

“We have no proof of who may have said it,” wrote a local prosecutor in a report released Wednesday as part of the police investigative file.

The university has announced several programs in response to the incident. All incoming students will now attend mandatory seminars on diversity, and student group leaders will be required to undergo training on “conducting effective dialogues and meaningful conflict resolution,” Young said in a letter to students.

University students also organized a campaign to send thousands of handwritten apology notes to the high school whose students had been touring campus.