What you need to know:
- News of the fresh carnage came as detectives just a few hundred miles (kilometers) away in Monterey Park were trying to piece together why Huu Can Tran gunned down revellers gathered at a dance studio for Lunar New Year on Saturday night.
An Asian farm worker was in custody Monday after seven of his colleagues were killed in front of children at sites in California, days after a mass shooter killed 11 people at a Lunar New Year celebration near Los Angeles.
The latest bloodshed to hit Asian Americans in California occurred at two farms around Half Moon Bay, a coastal community near San Francisco.
San Mateo County Sheriff Christina Corpus said seven people were killed and one injured in the twin shootings, and that a 67-year-old Half Moon Bay resident named Chunli Zhao had been taken into custody.
As the new tragedy unfolded, detectives at the southern end of the state were still probing what drove an elderly Asian immigrant to shoot dead 11 people gathered in celebration at a suburban dance hall -- before taking his own life as police closed in.
Both suspects used semiautomatic handguns in their assaults, and both appeared to have connections to at least some of their victims.
Corpus said deputies had been dispatched to two nurseries around Half Moon Bay, a rural spot south of San Francisco, mid-afternoon Monday.
Four people were dead at one of them and one critically wounded.
"Shortly thereafter three additional victims were also located deceased with gunshot wounds at a separate shooting scene," she told reporters.
"There's people that live at the location as well... it was in the afternoon when kids were out of school and for children to witnesses it is unspeakable," she said.
Corpus said Zhou then drove to a sheriff's substation in Half Moon Bay where ABC7 crews captured dramatic footage of his arrest as he was pulled to the ground by armed officers.
"Zhao was taken into custody without incident and a semi-automatic handgun was located in his vehicle," Corpus said.
Reports said the dead are Chinese farmworkers, and that Zhao had worked at one of the farms.
Probing the motive
News of the fresh carnage came as detectives just a few hundred miles (kilometers) away in Monterey Park were trying to piece together why Huu Can Tran gunned down revellers gathered at a dance studio for Lunar New Year on Saturday night.
Los Angeles County Sheriff Robert Luna said Monday that Tran, who had been arrested in 1994 for unlawful possession of a firearm, fired 42 rounds in the attack.
But, he said, much was still unknown.
"What drove a madman to do this? We don't know. But we intend to find out," he told reporters.
Luna confirmed officers had been told Tran may have been known to some of his victims, but said there was currently no evidence he was related to any.
News of a second mass shooting in California in less then 48 hours spread ripples of shock through the state, which already has some of the strictest firearm laws in the United States.
An exasperated Governor Gavin Newsom, who had earlier Monday been in Monterey Park where he lashed out at federal inaction over guns, called it another "tragedy."
"At the hospital meeting with victims of a mass shooting when I get pulled away to be briefed about another shooting. This time in Half Moon Bay. Tragedy upon tragedy," he tweeted.
Saturday night's mass shooting was the worst in the United States since a teenage gunman in Uvalde, Texas killed 21 people at an elementary school last May. All but two were children.
On Monday a picture began to emerge of the culprit in Monterey Park, a man who, according to his marriage license, had immigrated from China, and who had been a regular at the Star Ballroom Dance Studio in the past.
Tran's ex-wife told CNN the couple had met there two decades ago when he offered to give her informal lessons.
The woman, who did not want to be named, said they married a short time later, but the relationship did not last, with the divorce finalized in 2006.
She said Tran, who sometimes worked as a truck driver, was not violent, but could be impatient.
A man who said he had previously known Tran said he would complain about dance teachers, who, he claimed, would say "evil things about him", CNN reported.
He was "hostile to a lot of people there," the man told the broadcaster.
Detectives who searched a mobile home where Tran had been living in Hemet, 85 miles (140 kilometers) east of Los Angeles, recovered a rifle, electronics and ammunition, Luna said.
Police in the city said earlier this month Tran had made "fraud, theft, and poisoning allegations involving his family in the Los Angeles area 10 to 20 years ago."
'Her last dance'
The family of 65-year-old My Nhan said the tragedy was "still sinking in."
"She spent so many years going to the dance studio in Monterey Park on weekends," a statement said.
"It's what she loved to do. But unfairly, Saturday was her last dance.
Amid the grief, one tale of heroism has given hope as 26-year-old Brandon Tsay revealed how he grappled with Tran as the elderly man arrived at another dance studio, in what police believe was a planned second attack.
"He was hitting me across the face, bashing me in the back of my head, I was trying to use my elbows to get the gun away from him," Tsay told ABC.
"Finally, at one point I was able to pull the gun away from him, shove him aside, create some distance, point the gun at him, intimidate him, shouting, 'Get the hell out here. I'll shoot. Get away. Go.'"