When Lyndon McLeod fatally shot two men and three women in a rampage that included two tattoo parlors, a hotel and a private home in Denver last month, it didn’t come from nowhere.

In one of the novels from his self-published trilogy, he described killing people — and two of the characters who end up dead share names with his real-life victims. McLeod was also active on online forums where he touted masculine supremacy and disdain for the “weak.”

Denver police eventually shot and killed McLeod after he shot an officer. The police department had received a warning about McLeod about a year before the shootings, from a German man who grew concerned after reading McLeod’s books and online chats. But in a statement released after the shootings, Denver police said they had determined “there was not sufficient evidence to file criminal charges or a legal basis for monitoring McLeod at the time.” The department also told HuffPost that there were two previous law enforcement investigations into McLeod, but neither resulted in criminal charges.

McLeod’s case is an example of the ties between misogyny and easy access to guns that Everytown for Gun Safety highlights in a new report this week, which was shared with HuffPost ahead of its publication. The group documents at least six high-profile misogyny-driven mass shootings in the U.S. since 2014, and the ways that guns and hatred of women have served as a unifying tie for many far-right groups online.