"Police say the shooter was 57-year-old Samuel Cassidy, a Valley Transportation Authority employee who fatally shot the victims at about 6:30 a.m. local time. 'I never believed him, and it never happened until now,' Cassidy's ex-wife, Cecilia Nelms, told the Associated Press.  She also said Cassidy used to come home from work resentful and angry over what he perceived as unfair assignments. 'He could dwell on things,' Nelms also said." https://archive.li/P6nHs