The man who opened fire on his colleagues Wednesday at a San Jose rail yard, killing nine of them, was reportedly scheduled to attend a work disciplinary hearing over alleged racist remarks on the day of the massacre. Citing law-enforcement sources, NBC Bay Area reports that Samuel Cassidy’s colleagues at the Valley Transportation Authority had recently complained about his racist outbursts at work, and he was expected to be disciplined by bosses on Wednesday. That morning, the 57-year-old died of an apparent self-inflicted gunshot wound after shooting nine of his workmates dead. The scheduled disciplinary hearing has not been confirmed by law enforcement, but sheriff’s investigators have described Cassidy as “a highly disgruntled VTA employee.” The Wall Street Journal reported Thursday that U.S. Customs officers detained Cassidy in 2016 and found that he kept a black book “filled with lots of notes about how he hates the VTA,” as well as books about terrorism.