At least six people were injured in a shooting at a school campus in Oakland on Wednesday, California officials said. The shooting, which took place around 12:45 p.m., left at least three of the victims in critical condition. The condition of the other three victims was not shared by an Alameda County Sheriff’s Office spokesperson. A tweet from Oakland Mayor Libby Schaaf clarified that all six wounded were adults but provided few other details. “Today’s gun violence at Sojourner Truth school shocks the soul—our schools are sanctuaries for our children,” Schaaf said. Authorities did not immediately provide information on any possible suspects or arrests. The Oakland campus houses at least three schools, according to The New York Times, with Schaaf saying the shooting had occurred at the Sojourner Truth Independent Study school. Some teachers at the nearby Bay Area Technology School told the Times they had heard gunshots around the time of the incident.