“Keep Australia White.”

That's the message Melbourne schoolteachers found papered on the walls of their institutions this weekend. White supremacists broke into three schools and hung at least 60 racist posters. Some fliers offered up hateful anti-immigrant messages. One read “Stop the hordes.” Another called to legalize the killing of Jewish people. A third encouraged young people to “join your local Nazi group.”

One depicted a grasping, hooknosed Jew — a classic image in Nazi propaganda — alongside the words “Multiculturalism,” “Degeneracy” and “Reject Jewish Poison.”

The vandals targeted a private high school, a magnet school and a school in a suburb. Most of the fliers were found by educators and removed before students arrived for class Monday morning.

“There's African kids, Asian kids, white kids and subcontinental kids all playing next to these covered-up posters,” a janitor who found the fliers at one of the schools told an Australian radio station. “It's just gutless, cowardly.”

The group Antipodean Resistance has asserted responsibility. It describes itself as a neo-Nazi group, “the Hitlers you've been waiting for.” Some members posted pictures of themselves with the fliers this weekend, along with a statement: “These high schools are overrun by nonwhites, which is encouraged by our traitorous government.” Though the organization claims a national following, police say there are only a handful of members in the Melbourne area.

Political leaders and educators soundly denounced the crime. “This is incredibly concerning for our school communities,” the education minister for the state of Victoria, James Merlino, told the Guardian newspaper. He described the posters as “vile and disgusting” and said the perpetrators “should be ashamed of themselves.”

Victoria police are investigating. The fliers violate a 2001 religious tolerance law that prohibits actions that incite or encourage hatred of a particular group of people because of their religious beliefs. The measure specifically calls out racist graffiti, racist posters or stickers and racist abuse in a public place.

There are about 120,000 Jews in Australia. Jewish organizations say anti-Semitism is on the rise in the country. According to a report by the Executive Council of Australian Jewry, attacks on Jews and Jewish property jumped 10 percent in 2016; Jewish community groups logged a total of 210 incidents. That included physical assaults and harassment, along with vandalism and graffiti. In one instance, a 22-year-old was punched in the neck and called an expletive as he walked home from a synagogue. In another, onlookers threw eggs at Jews as they walked home from Friday night services.

Holocaust-denial pamphlets were distributed at several universities, along with neo-Nazi brochures calling for the killing of all Jews. Two vehicles were firebombed, the glass door of a synagogue was broken, and vandals covered the walls of a synagogue with messages such as “f‑‑‑ing Jew” and “die Jeue.”

Other groups have been targeted, too. In July, the Antipodean Resistance plastered anti-Chinese posters in two Melbourne universities. The fliers were written in poor Chinese and read “Attention! This is a place that prohibits Chinese people to enter. Any offense is subject to prosecution or possible deportation.”

University officials were quick to denounce the fliers, but some Chinese students said the vandalism was jarring. “I felt enraged, thinking of how Chinese overseas communities have always been isolated, unjustly labeled and even attacked,” Melinda Mengying Li, 23, who had recently arrived in Melbourne to begin a master’s degree, told the New York Times. “I hoped on campus there could be an atmosphere of equality, mutual respect and mutual improvement.”