(EVANSTON) Northwestern University officials are investigating reports that multiple students may have been drugged and sexually assaulted at a fraternity house last month in north suburban Evanston.

The university’s Sexual Harassment Prevention Office received a report Thursday that four female students “were possibly given a date-rape drug” while attending an event at the Sigma Alpha Epsilon fraternity house in Evanston on Jan. 21, according to a security alert on the university’s website. Two of the students believe they were sexually assaulted.

Another student reported that she was sexually assaulted, possibly with the use of a date-rape drug, at another fraternity house on Thursday, the university said. It was not immediately clear where that incident occurred.

The Sexual Harassment Prevention Office and Northwestern University Police are investigating the incidents, according to the university. Anyone with information about them is asked to contact the university’s Title IX coordinator at [email protected] or call university police at (847) 491-3456.

Nell Maltman, 29, a graduate student on campus, told the Chicago Sun-Times the idea that sexual assault could happen at such a “progressive school” is “horrible.”

“You wouldn’t think that sort of thing would be happening,” said Maltman, who was in a sorority, but not at Northwestern, as an undergraduate. “I guess it happens everywhere.”

Maltman said she’s been pleased with how the university has handled the reports.

“We were alerted right away when this report came out — I heard about it last night,” she said. “They sent out an email, they gave resources to students. They certainly addressed it head-on by telling the community about it.”

Lindsay Wilson, 18, is in a sorority at Northwestern. She said she began hearing the reports of alleged misconduct at Sigma Alpha Epsilon about a week ago.

“We had a philanthropy event with them and cancelled it and did it on our own,” Wilson said.

Wilson said she didn’t know the details of the reports now making the rounds on campus.

“I’ve never felt unsafe here before, but I guess now it makes you wonder,” she said.

The Sigma Alpha Epsilon headquarters, which is in Evanston near the university, also has launched an investigation into the allegations, according to a statement from Brandon E. Weghorst, a spokesman for the national fraternity. The statement notes that the fraternity will work with university administrators and chapter leaders to gain more information.

“Any form of assault or sexual misconduct by anyone, brother or not, college man or not, is completely unacceptable, and we do not tolerate actions that are inconsistent with our mission. Sigma Alpha Epsilon always is committed to the safety and well-being of our members and the guest with whom they interact, and that commitment includes making sure our members provide a safe, enjoyable environment in their homes,” according to the statement. “When incidents are brought to our attention, we take immediate action, and will not hesitate to take corrective actions or impose sanctions on any member or chapter that fails to follow the stringent guidelines we set forth.”

The Evanston Police Department said the matter is being handled by Northwestern and Evanston police are not involved. Northwestern University Police referred all questions to the Department of University Relations.

Despite the reports circulating on campus, freshman Isabella Rischall, 18, says she generally feels safe at Northwestern. She attends fraternity parties, though she is not in a sorority.

“I’ve been to different parties — it’s never been something that’s on my mind, but then getting the email (from administrators) was concerning,” Rischall said. “I hope Northwestern does something about it, rather than brush it under the table.”

She said she doesn’t think she’ll change her social habits in light of the reports.

“I keep my drink close. I don’t set it down and pick it up later,” she said. “It’s a just-in-case kind of thing.”