At least two U.S. colleges with chapters of the campus group Students for Justice in Palestine (SJP) have reported seeing posters linking the group to the Islamic terror group Hamas, which controls the Gaza Strip. The posters, branded with the hashtag #JewHaters, turned up at the University of California, Los Angeles and the University of Massachusetts Amherst this week. The posters coincide with Israeli Apartheid Week, an anti-Israel event held in more than 120 cities worldwide.

“I have no apologies for the posters,” David Horowitz, a Jewish right-wing activist and founder of the David Horowitz Freedom Center, told the Jewish Journal. His group has claimed responsibility for them. “They were done in a sort of surprise way to attract attention, which they have succeeded in doing. I’m proud of being behind this.”

Horowitz said the posters belong to his campaign “Jew Hatred on Campus,” a report by his think tank that includes a list of “Top 10” colleges that have had numerous anti-Semitic attacks on campus. The group’s study said 54 percent of Jewish American college students experienced some form of anti-Semitism in the 2013-2014 academic year.

One of the posters on the UCLA campus is based on a photo taken during the Israel-Gaza conflict last summer of an apparent execution. Two gunmen stand over a man on his knees with a bag over his head. Another photo shows a bloodied man dragged by a motorcycle. Both have “Students for Justice in Palestine” on the top and “#JewHaters” on the bottom.

“We were surprised to see it here. The imagery is shocking," Evan Scribner, treasurer for Students for Justice in Palestine at UMass Amherst, told the Republican. While the university has criticized the posters, Scribner says some members of the group "are pretty nervous especially considering the shootings in North Carolina," referring to the shooting of three young Muslims in their apartment complex this month. He says campus security will be present at events during Israel Apartheid Week and student volunteers have offered to walk with students who feel unsafe around campus.

At UCLA, Jewish groups Hillel, Chabad, Bruins for Israel, Jewish Awareness Movement and J Street U issued a joint statement condemning the posters and sent volunteers to remove them.

“I’ve spent a lot of my time criticizing actions that SJP has taken,” Avinoam Baral, president of UCLA’s student government and a prominent pro-Israel supporter on campus, told the Jewish Journal. “[But] stooping down to the level and calling people ‘Jew hater’ is something that I think, quite frankly, is very inappropriate and very offensive.”

Students for Justice in Palestine is a national organization with almost 100 chapters on American and Canadian campuses. The group advocates for Palestinian equal rights and the cessation of Israeli settlements in the Gaza Strip and West Bank and Israel’s military presence in the two territories.

SJP has been linked to several contentious incidents on campuses. In one case, the group’s chapter at Loyola University Chicago was suspended after members hurled insults at students manning a table for Birthright Israel. Hillel chapter President Talia Sobol said protesters asked “How does it feel to be an occupier?” and “How does it feel to be guilty of ethnic cleansing?” A video was posted on social media by an SJP member and was later removed, according to the College Fix. Last year, an SJP chapter was suspended at Northeastern University in Boston after members posted mock eviction notices across campus, in an apparent imitation of signs posted on Palestinian homes slated for demolition by Israeli authorities.

Some of the group’s most prominent leaders are Jewish students. Horowitz says this is one of the reasons why his organization started this campaign in the first place. “I hope that some of these Jewish students will wake up and join us,” he said.