Patrick White, the man who police say opened fired on the CDC headquarters, blamed his depression on the COVID-19 vaccine, multiple outlets reported.

A union representing workers at the CDC said the incident was not random and “compounds months of mistreatment, neglect, and vilification that CDC staff have endured.”

Patrick White is believed to have struggled with his mental health, according to that information. As he grappled with those issues, sources said, White had become increasingly fixated on the COVID-19 vaccine as a source of his grievances.