Toronto police are investigating a possible hate crime after anti-Semitic notes were found on the doors of several units at a condo building in the Willowdale neighborhood of the city.

Post-it notes bearing a swastika and reading “No Jews” were found on the front doors of several Jewish residences in the building, reported the CP24 news channel.

Some of the notes contained anti-Semitic slurs and some residents reported that their mezuzahs had been vandalized.

A total of seven residents reported receiving the notes or having the mezuzahs on their doors vandalized.

Speaking with CP24, one resident who came home to find her mezuzah vandalized said she was “shocked.”

“It’s naturally very disturbing,” the resident, Helen Chaiton, said. “I come from the Holocaust – my parents came to Canada in 1948 after the war. So I’m very familiar with anti-Semitism and I know historically what ensues.”

It is unclear who left the notes, though residents said they believe it may be someone who lives in the building. The building does not appear to have surveillance cameras in the hallways, according to CP24.

Toronto police spokesman Mark Pugash told the news channel that while the city has not seen a notable increase in hate crimes this year, they are taking the latest incident of a targeted attack “extremely seriously.”

“Every hate crime is concerning, not only to people on the receiving end but everyone in this city is concerned, as they should be,” Pugash said. “We take this extremely seriously, our investigators are very, very experienced.”

Toronto Mayor John Tory condemned the incident, saying that there is no place in the city for those who seek to divide Torontonians.

“Anti-Semitism has no place in Toronto. Our Jewish residents should not have to face hatred on their doorsteps,” Tory said in a statement. “These acts, and the people who carry them out, do not represent Toronto or Torontonians.”

Toronto police said last year that it found a decrease of 8 percent in the volume of hate crimes in the city in 2015 (134 compared with 146 in 2014) - but the Jewish community remained at the top of the list of victims of hate crimes.

The police’s annual report on hate and bias crimes found that the number of hate crimes that were directed against the Jewish community in 2015 was the largest compared to other communities.