Authorities have not revealed what the explosive materials were and have not identified the type of firearms they say they found in Snyder's apartment.
University officials would not release details about the injuries Snyder suffered, but they said he was released from the hospital Sunday afternoon and booked into the Yolo County Jail. Bail was set at $2 million.
Snyder — who was working in a temporary position as a junior researcher in a campus chemistry lab — was placed on investigatory leave while the incident was being investigated, university spokeswoman Claudia Morain said Sunday.
Snyder previously received a bachelor's degree in chemistry from UC Davis in 2004 and a Ph.D. in chemistry in December 2011.
After earning his doctorate, he held a temporary one-year research appointment through UCSF that allowed him to work at UC Davis. That position ended in November. His current temporary job with UC Davis began in December was due to expire Jan. 31, Morain said.