Four people died after 14 people were shot at a family gathering in Stockton in northern California on Saturday night, police said.
The shooting took place at a child's birthday party, Stockton's Vice Mayor Jason Lee said in a Facebook post.
"I am in contact with staff and public safety officials to understand exactly what happened, and I will be pushing for answers," he said.
Police said they received reports shortly before 6:00 p.m. local time (0600 GST) of a shooting that occurred near the 1900 block of Lucile Avenue in Stockton.
"We can confirm at this time that approximately 14 individuals were struck by gunfire, and four victims have been confirmed deceased," San Joaquin County Sheriff's Office said in a post on X.
"This is a very active and ongoing investigation, and information remains limited. Early indications suggest this may be a targeted incident, and investigators are exploring all possibilities."
Authorities have not provided any details about a shooter.
Israeli Prime Minister Benjamin Netanyahu submitted a request to the country's president on Sunday for a pardon in his years-long corruption trial, arguing that criminal proceedings were hindering his ability to govern and a pardon would serve the interests of Israeli society.
The death toll mounted to over 600 from floods and landslides caused by torrential rains across three countries in Southeast Asia, officials said on Sunday, as relief efforts for tens of thousands of displaced people continued over the weekend.
Sri Lanka's Disaster Management Centre (DMC) said on Sunday that the death toll from Cyclone Ditwah, which has been affecting the country in recent days, has climbed to 159, with 203 still missing.
More than a thousand people turned out on Sunday to pay tribute to the victims of Hong Kong's deadliest fire in more than 75 years, as Beijing warned it would use a national security law to crack down on any "anti-China" protest in the wake of the fire.
President His Highness Sheikh Mohamed bin Zayed Al Nahyan has said that Commemoration Day, on November 30, is a cherished national occasion on which the nation honours the memory of its courageous heroes who gave their lives for the UAE, exemplifying the highest ideals of sacrifice in defence of their country and its values.
His Highness Sheikh Mohammed bin Rashid Al Maktoum, Vice President and Prime Minister of the UAE and Ruler of Dubai, said that on Commemoration Day the spirit of patriotism fills the hearts of all Emiratis, and the nation takes pride in the sacrifices of its martyrs.
UAE President His Highness Sheikh Mohamed bin Zayed Al Nahyan has sent a message of condolence to President Prabowo Subianto of Indonesia over the victims of floods and landslides on Sumatra Island, resulting in hundreds of deaths and injuries.