Taiwanese are heroes in California church shooting

A gunman opened fire in a Southern California church during a lunch involving Taiwanese, killing one person and wounding five before churchgoers grabbed him and hog-tied his legs with an electrical cord.

Police responded to the incident that unfolded at about 1.30pm at the Geneva Presbyterian Church in Laguna Woods and arrested an Asian man in his 60s.

Orange County undersheriff Jeff Hallock said churchgoers displayed "exceptional heroism and bravery in intervening to stop the suspect. They undoubtedly prevented additional injuries and fatalities."

Jerry Chen, 72, said about 40 congregants had gathered in the fellowship hall for a lunch after a morning service to welcome former pastor Billy Chang, who served the church for 20 years before moving back to Taiwan two years ago.

The victims were all of Taiwanese descent aged from 66 to 92.

Most of the church's members are elderly, highly educated Taiwanese immigrants, Chen said.

No motive had been established, Hallock said, adding that the shooter "is not believed to live in the area and investigators are working to determine whether he has any connections to the church or its congregants."

Democratic Congresswoman Katie Porter, who represents Orange County in Washington, called the attack shocking, "especially less than a day after a mass shooting in Buffalo."

That shooting saw an 18-year-old white gunman kill 10 people and wound three - almost all of them black - at a grocery store in Buffalo, New York state. Authorities called it a "racist" rampage.

Mass shootings are common in the United States, where efforts at tightening gun laws have fallen short in the face of the powerful firearms lobby.