Two days after students discovered swastikas outside Durfee Hall on Old Campus, the Yale Police Department is continuing its investigation into the incident — but leads remain elusive.

Yale College Dean Jonathan Holloway, who in a Monday night email encouraged members of the Yale community to submit tips to the YPD, confirmed Tuesday that the YPD is actively investigating the case. But on Tuesday, YPD Assistant Chief Steven Woznyk said the police station has not received any tips about suspect perpetrators or their motivations. Woznyk added that any tips should be directed to the YPD either directly or through an anonymous text messaging service.

Holloway said that he is unaware if Sunday’s incident was related to a similar one in September, when two swastikas were found on whiteboards in Vanderbilt Hall.

The swastikas outside of Durfee were reported by a student at 10:30 p.m. Sunday night to Holloway and Rabbi Leah Cohen, executive director of the Slifka Center for Jewish Life and senior Jewish chaplain. The student, who spoke on the condition of anonymity, said it was surprising that news of the graffiti took so long to surface.

The student added that finding the perpetrators will be difficult.

“[The incident] happened at the end of [Family] Weekend when there’s a lot of different people around, including security,” the student said. “It could have been anyone.”

The student who reported the case said that although the administration has been very supportive, it was initially unclear to whom they should report the swastikas. There is no campus equivalent to a Title IX coordinator designated to support victims of hate crime, the student added.

On Tuesday, students and administrators alike expressed shock and abhorrence at the incident.

University President Peter Salovey said he hopes the perpetrator is not affiliated with Yale. Salovey added that the graffiti is a challenge to an atmosphere of respect on campus.

The incident provoked a quick response from an array of campus groups, who transformed the sidewalk outside of Durfee Hall into a mural castigating intolerance Monday night.

In addition to the mural outside Durfee, other messages of support were drawn outside Vanderbilt on Tuesday, including one that said “Justice, Justice Shall You Pursue” in English and Hebrew.

Shayna Otis ’16 managed a table on Old Campus on Tuesday afternoon where students could share their thoughts with each other. Visitors to the table were invited to write something they took personal pride in on a slip of paper, place it in a bowl and then exchange it for a slip a previous student had written.

“Well over 100 students have come to fill out to a card, and hundreds stopped to look,” Otis said, adding that not many had known about the swastikas beforehand.

Rabbi Shua Rosenstein of Chabad at Yale, who also helped coordinate the table with Otis, said students he had spoken to were distressed by the Sunday incident.

“They were very hurt that at a place like Yale something like this should happen, and that pain is understandable and very real,” he said. He added his hope that a negative action such as this will act as a prompt for further demonstrations of good.

Holloway applauded the students who took part in the creation of the mural.

“I’m enormously proud of them for taking that action,” he said. “I was moved by it.”

Stephan Riemekasten ‘17, a student from Germany, said the swastikas were a chilling reminder of his home country’s past. Riemekasten said he was taught from an early age that signs of anti-Semitism were strictly forbidden in German society.

Riemekasten said he knew to expect comments from peers about his German heritage and the graffiti on Tuesday.

“I’m always going to be judged because I’m German, and I’m always going to be connected to [the Nazi’s] policies even though they’re very different from my actual beliefs,” Riemekasten said. “[The graffiti] was disrespectful to all kinds of people. The reaction from the students was so awesome, and it reminded me that that’s why I decided to come here.”

Jonathan Pierce, former International President and current spokesperson of the executive board of Alpha Epsilon Pi — an international Jewish fraternity — said AEPi brothers across the country are showing their support in response to recent instances of anti-Semitism on college campuses.

“We are doing everything we can to preserve the safety of our brothers, while still encouraging them to be advocates of Judaism and of Israel,” he said.

Sunday’s incident was not the first instance of swastikas in public places on campus this year.

Branford Master Elizabeth Bradley said she was shocked when, in early September, two swastikas were discovered on whiteboards in Vanderbilt Hall, which houses freshmen in Branford. When that incident occurred, Bradley and Branford Dean Hilary Fink sent an email to all freshmen and freshman counselors within the college to offer support. Rather than alert the entire student body, Bradley said she thought it best to monitor the situation from within the Branford community.

Bradley said that to her knowledge, the September incident was the first of its kind in Branford, and that she was invested in monitoring the situation.

“This was the first and only event that I can remember experiencing, so we said, ‘let’s start this way and keep our eye on it,’” she said.

Despite the sense of shock on campus following Holloway’s Monday night email, Yale’s campus has not been immune to acts of anti-Semitism in the past few years.

In 2013, graffiti threatening arson at the Slifka Center was discovered at Sterling Chemistry Laboratory by YPD.

University Vice President for Global and Strategic Initiatives Linda Lorimer told the News in May 2013 that the Chemistry lab graffiti prompted an investigation involving University officials, YPD, the Federal Bureau of Investigation and the Connecticut chapter of the Anti-Defamation League.

In 2008, Swastikas fashioned out of snow were also found on trees in the middle of Old Campus, though no perpetrators were ever determined.