On Tuesday afternoon, Jesse Van Rootselaar, 18, grabbed two firearms from her home and, the authorities in British Columbia said, killed her mother and 11-year-old brother. Then she traveled a mile to the Tumbler Ridge Secondary School and killed five students and one educator before turning her weapon on herself.
The mass shooting, which also left two children injured with gunshot wounds, has sent shock waves across Canada, where such violence is rare, and has devastated the small rural community of 2,400 people.
An investigation of Ms. Van Rootselaar’s online life offers a chronicle of a young person’s gradual descent into mental health crises and radicalization into extreme violence.
