Alan Kats had angry words for two people he came looking for at a low-rise office building in Toronto on Monday afternoon — a witness heard arguing before the gunshots — but he also had much more in mind. He came to kill them, and then kill himself.

Kats, 46, left his wife a note before setting off to the North York office, where he found Arash Missaghi, described by a judge as a “predatory fraudster”, and Samira Yousefi, a pushy mortgage agent, who he blamed for defrauding the couple of their home and savings through an investment swindle that Missaghi had unrelentingly pulled on many people over many years, according to victims and police allegations.