On Wednesday, a shooting occurred at an Oakland school, injuring six people, according to officials.
On Twitter, Mayor Libby Schaaf said that all of the victims were adults who were receiving medical care.
According to James Jackson, CEO of the Alameda Health System, two people were in critical but stable condition, while a third was described as stable at a nearby trauma centre.
Injuries sustained by a fourth individual were not considered life-threatening, according to Assistant Chief Darren Allison of the Oakland Police Department.
Shortly before 1 p.m., Allison informed reporters that a shooting had taken place on a campus housing four schools, including a middle school and high school, in the city's Eastmont Hills area.
Neither a motive nor a suspect were suggested by Allison. He said they are looking for one gunman, but it's possible others were involved.