Various sources reporting today;
Police in Northern California responded to a "mass casualty overdose" situation on Saturday that resulted in one death and a dozen people hospitalized.
Authorities said that the incident was caused by exposure to the deadly opioid fentanyl, which also affected two responding officers, according to NBC News.
Mike O'Brien, a police captain in Chico, Calif., said at a news conference that four of the victims were in critical condition