Eight years after a deadly Toronto attack brought the "incel" movement into the public spotlight, reports have again bought concerns about the ideology following Monday’s deadly shooting in Montreal's Côte-des-Neiges neighborhood. The incident left a Montreal police officer and a civilian dead, while a second officer was seriously injured before the suspect was "neutralized," according to authorities. Police later confirmed that one officer, one civilian, and the suspect had died.“It is with immense sadness that we confirm the death of one of our police officers in the line of duty,” the Service de police de la Ville de Montréal (SPVM) said in a statement.Montreal police identified the slain officer as Mohamed Lamine Benredouane, 34, who had served with the force since 2021. CBC News confirmed the civilian killed was Michael Mizrahi.— SPVM (@SPVM) While authorities have not publicly disclosed a motive, reports from multiple media outlets have focused on an alleged manifesto and possible links to incel ideology.Why is the shooting being linked to an incel manifesto?According to AFP, citing French-language public broadcaster Radio-Canada, the gunman was connected to "incel" ideology, a misogynistic worldview that was also linked to the perpetrator of the 2018 Toronto vehicle-ramming attack that killed 10 people.CBC also reported that the suspected shooter had allegedly distributed a violent incel manifesto targeting women.Authorities, however, have not officially confirmed the contents of any manifesto or publicly attributed a motive to the attack.Several online publications, including Finaltrends, The Suburban, and TVA Nouvelles, identified the suspected shooter as "Seth Hatfield" from Alberta. However, that identity has not been confirmed by authorities.Canadian far-right media outlet Rebel News also published excerpts from the alleged manifesto and described him "a Jew-hating Communist censor," though the authenticity of the document has not been verified by law enforcement.As per the so-called ‘preamble’ of the alleged document, the writer was concerned about the ‘terrible loneliness, isolation, and social degradation’ people of various ages in the modern western world are going through.What is an incel?The term "incel" is short for "involuntarily celibate." It originally emerged online as a label used by people who described themselves as unable to form romantic or sexual relationships despite wanting them.Over time, some online incel communities became associated with extremist beliefs, particularly misogynistic political views that blame women for members' perceived romantic failures.Security experts and researchers have warned that certain corners of the incel movement have evolved into online spaces where resentment, hatred, and violence are sometimes glorified. Several violent attacks in North America, Australia, and elsewhere have been linked to individuals who identified with or promoted incel ideology.Montreal shooting timelineThe shooting unfolded Monday, June 22 in Montreal's Côte-des-Neiges neighborhood. Montreal police issued an emergency alert warning residents about an "armed and dangerous suspect" and instructed people to shelter indoors, lock their doors and stay away from windows.Authorities later lifted the shelter-in-place order and said the immediate threat to the public had ended.The violence occurred in an area that includes kosher markets and restaurants and has a significant Jewish population. The civilian killed, Michael Mizrahi, has been identified as a member of Montreal's Jewish community.Investigators have not announced whether the location or victims were specifically targeted, and no official motive has yet been released.