"Sadly, we once again mourn the lives lost and for those injured in yet another horrendous act of gun violence," Newsom said in a statement Sunday. "Jennifer and I send our heartfelt condolences to the family, friends, and to the wider community impacted by this terrible tragedy."
"What we do know at this point is that another mass casualty shooting has occurred, leaving families with lost loved ones, multiple individuals injured and a community in grief. The scourge of gun violence continues to be a crisis in our country, and we must resolve to bring an end to this carnage," his statement continued.
Gunfire rang out in downtown Sacramento early Sunday morning, killing six people and injuring 12 others, according to police.
Sacramento Police Chief Kathy Lester said Sunday that officers were patrolling the downtown area at about 2 a.m. when they heard gunfire.
Police found a large crowd gathered on the street when they arrived on the scene, and six people dead. Ten other people were either transported or took themselves to a hospital. No information was given on their conditions.
Lester called the shooting "a really tragic, unfortunate situation."
One video on Twitter appeared to show people running through the street as the sound of gunfire could be heard in the background.
No suspects have been arrested and the number of shooters is unknown as of Sunday morning. It is unclear if the victims were targeted.
"Right now our investigators are arriving the scene," Lester said. "This is very preliminary."
President Biden released a statement saying in part, "Today, America once again mourns for another community devastated by gun violence. In a single act in Sacramento, six individuals left dead and at least a dozen more injured. Families forever changed. Survivors left to heal wounds both visible and invisible."
The statement then goes on to say, "But we must do more than mourn; we must act. That is why my Administration has taken historic executive action to implement my comprehensive gun crime reduction strategy — from standing up gun trafficking strike forces to helping cities across the country expand community violence interventions and hire more police officers for community policing."
Newsom has been an outspoken gun control advocate, including supporting a bill in February that would allow Californians to sue gun manufacturers and distributors. The bill was modeled after Texas's recent heartbeat bill.
"It’s time to go on the offensive with new measures that empower individuals to hold irresponsible and negligent gun industry actors to account, crack down on shameful advertising that targets our kids and more," Newsom said at the time. "This is not about attacking law-abiding gun owners – it’s about stopping the tragic violence ravaging communities across the country."
Newsom announced late last year that he directed his administration to work with the state legislature and develop a gun control measure modeled after Texas' recent abortion ban. The Texas law allows residents to sue anyone who helps a woman get an abortion after a heartbeat can be detected.
The Associated Press contributed to this report.
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