'If someone was to go postal, it'd be him': Co-workers with conflicts tried to warn officials about San Jose shooter in 2020

New evidence was released on Thursday about the man accused of killing nine coworkers during a mass shooting in San Jose.

"The VTA released documents Thursday showing a history of insubordination and conflict at work for the man who opened fire on his colleagues, killing nine of them," ABC 7 reported. "The first batch of documents released show there were four incidents involving Sam Cassidy that were "elevated to management," some of which resulted in disciplinary action.

"The first occurred on July 16, 2019, said VTA, when Cassidy was sent home without pay for two days for insubordination. The agency says he refused to 'follow company policy in signing out a two-way radio that was necessary to perform his job.' In January 2020, Cassidy had a verbal altercation with a coworker," ABC 7 reported. "At the time, the coworker made a report to a supervisor, that another unnamed employee said about Cassidy: 'He scares me. If someone was to go postal, it'd be him.'"

"VTA documents describe another incident in October 2020, when Cassidy refused to take a mandatory CPR certification, citing COVID-19 as a concern," ABC 7 reported. "Finally, in November of last year, Cassidy misused radio equipment and then abruptly left for the day."

Watch: