One person was dead and four others in "critical" condition after a shooting at a church near Los Angeles, law enforcement said Sunday, just one day after a gunman killed 10 people at a grocery store in New York state.
Parishioners were attending a banquet following a morning church service when the gunman began his rampage, authorities said.
"That group of churchgoers displayed what we believe is exceptional heroism, and bravery," Hallock said. "They undoubtedly prevented additional injuries and fatalities."
Investigators were still searching for a motive, he said, adding that the alleged gunman, who was not injured during the incident, was believed to be an Asian adult male in his 60s.
The victims were mostly Asian and mostly of Taiwanese descent, the Los Angeles Times reported, citing authorities.
"One person is confirmed deceased at the scene," Hallock said. "Four others are critical and one other victim sustained minor injuries." All were adults.
Law enforcement said an emergency call had come from Geneva Presbyterian Church at 1:26 pm (20:26 GMT) Sunday afternoon.
They were additionally waiting for help from a translator in interviewing members of the congregation and the alleged assailant, Hallock told reporters.
The office of California Governor Gavin Newsom said it was working with local officials to monitor the situation.
"No one should have to fear going to their place of worship. Our thoughts are with the victims," the office tweeted.
Democratic Congresswoman Katie Porter, who represents Orange County in Washington, called the shooting "upsetting and disturbing news, especially less than a day after a mass shooting in Buffalo."
"This should not be our new normal."
According to the sheriff's department, the church is located in the town of Laguna Woods, 45 miles (70 kilometers) southeast of Los Angeles.
The latest shooting comes one day after an 18-year-old white suspect shot dead 10 people and wounded three others -- almost all of them Black -- a grocery store in Buffalo, New York in what officials are calling a "racist" rampage.
Mass shootings have become shockingly common in the United States, where past efforts at tightening the nation's gun laws have generally fallen short in the face of the nation's powerful gun lobby -- even after horrific gun massacres.