A gunman has shot dead one person and critically injured five more after opening fire in a church.
The man carried out the shooting during a lunch banquet on Sunday, killing one person and wounding five, before churchgoers detained him and hog-tied his legs with an electrical cord, authorities said.
Police responded to the incident that unfolded at about 1.30pm (9.30pm British time) at the Geneva Presbyterian Church in Laguna Woods and arrested an unidentified suspect in his 60s, Orange County Undersheriff Jeff Hallock told a news conference.
"That group of churchgoers displayed exceptional heroism and bravery in intervening to stop the suspect. They undoubtedly prevented additional injuries and fatalities," he said.
One person died at the scene while four other victims were critically wounded.
Another person suffered minor injuries, he said.
All of the injured were taken to hospitals.
About 30 to 40 people were in the church when the shooting occurred, Hallock said.
"At this time, we do not know what the suspect's motive may be or whether he had an intended target, or whether this is even a hate-related incident," Hallock said, adding that authorities believe the suspect does not live in the area.
Two handguns were found at the scene.
"No one should have to fear going to their place of worship. Our thoughts are with the victims, community, and all those impacted by this tragic event," Governor Gavin Newsom's office said on Twitter.
The congregation had just finished eating lunch and were taking photos with a pastor who was returning after two years in Taiwan when the shooting started, Jerry Chen, 72, who was in a nearby kitchen at the time, told the LA Times.
“I heard the gun sounds,” he said. “Then I heard two or three more gunshots. He was just randomly shooting. I saw some people fall down or go under the table. I knew something was wrong. I called 911.”
The pastor hit the gunman with a chair when the shooter paused to reload his weapon, Chen said, and other members of the congregation tackled him.
Tom Cramer, leader of the Presbytery of Los Ranchos and a former pastor at the Geneva Presbyterian Church, told the newspaper: “This is a shock to us that anything like this would happen.”
It was at least the second mass shooting of the weekend in the United States, which has been plagued with gun violence in recent years.
In Buffalo, New York, on Saturday, a white 18-year-old man opened fire at a supermarket in a mostly black neighbourhood, killing 10 and wounding three in what authorities described as a purely racist attack.
