Seven people were killed in two related shootings Monday at a mushroom farm and a trucking firm in a coastal community south of San Francisco, and a suspect was in custody, officials said.
San Mateo County Board of Supervisors President Dave Pine says four people were killed at the farm and three at the trucking business on the outskirts of Half Moon Bay, a city about 30 miles (48 kilometers) south of San Francisco.
The police have arrested 67-year-old Zhao Chunli in connection with the shooting, Pine said.
It wasn't immediately clear how the locations were connected, though Pine said the suspect worked for one of the businesses. He called the suspect a "disgruntled worker."
California state Sen. Josh Becker, who represents the area, said people were killed in separate shootings. San Mateo County Supervisor David Canepa tweeted that one shooting happened at a mushroom farm.
The shootings happened as investigators searching for a motive in the worst mass shooting in Los Angeles County history say a search of the gunman’s home discovered a rifle, hundreds of rounds of ammunition and evidence he was manufacturing gun silencers.
Los Angeles Sheriff Robert Luna said Monday that investigators have not yet established Huu Can Tran’s motive in the massacre, which happened during a celebration of Lunar New Year at a Monterey Park dance hall.
Interactive: Find out more about mass killings in the U.S.
Interactive: Number of mass killings by year
Interactive: Mass killings by location scaled by number of victims
Interactive: Search mass killing incidents
Interactive: Timeline of mass killings scaled by number of victims killed
Interactive: Number of mass killings and victims killed this year compared with previous years
Interactive map: People killed by shootings, per 100,000 residents
22 of America's deadliest mass shootings in the past 10 years
July 20, 2012: Aurora, Colorado
Incident date: July 20, 2012 City/county: Aurora, Colorado Killed: 12
Family members stand outside Gateway High School where witnesses were brought for questioning after a gunman opened fire at the midnight premiere of The Dark Knight Rises Batman movie Friday, July 20, 2012 in Aurora, Colo.
Dec. 14, 2012: Newtown, Connecticut
Incident date: Dec. 14, 2012 City/county: Newtown, Connecticut Killed: 26
Parents leave a staging area after being reunited with their children following a shooting at the Sandy Hook Elementary School in Newtown, Conn., where a gunman opened fire, leaving 26 people dead, including 20 children on Dec. 14, 2012.
Sept. 16, 2013: Washington, D.C.
Incident date: Sept. 16, 2013 City/county: Washington, D.C. Killed: 12
A police boat patrols near the scene of a shooting at the Washington Navy Yard on Monday, Sept. 16, 2013, in Washington. At least one gunman opened fire inside a building at the Washington Navy Yard.
June 17, 2015: Charleston, South Carolina
Incident date: June 17, 2015 City/county: Charleston, South Carolina Killed: 9
Worshippers embrace following a group prayer across the street from the scene of a shooting at Emanuel AME Church, Wednesday, June 17, 2015, in Charleston, S.C. A white man opened fire during a prayer meeting inside the historic black church, killing multiple people, including the pastor, in an assault that authorities described as a hate crime.
Oct. 1, 2015: Roseburg, Oregon
Incident date: Oct. 1, 2015 City/county: Roseburg, Oregon Killed: 10
A woman is comforted as friends and family wait for students at the local fairgrounds after a shooting at Umpqua Community College in Roseburg, Ore., on Thursday, Oct. 1, 2015.
Dec. 2, 2015: San Bernardino, California
Incident date: Dec. 2, 2015 City/county: San Bernardino, California Killed: 14
Authorities search for a suspect following a shooting that killed multiple people at a social services facility Wednesday, Dec. 2, 2015, in San Bernardino, Calif.
June 12, 2016: Orlando, Florida
Incident date: June 12, 2016 City/county: Orlando, Florida Killed: 49
Police officers direct family members away from a fatal shooting at Pulse Orlando nightclub in Orlando, Fla. A gunman massacred 49 people and wounded many others at the gay nightclub.
Oct. 1, 2017: Las Vegas, Nevada
Incident date: Oct. 1, 2017 City/county: Las Vegas, Nevada Killed: 58
In this Oct. 3, 2017, file photo, windows are broken at the Mandalay Bay resort and casino in Las Vegas, the room from where Stephen Craig Paddock fired on a nearby music festival, killed 58 and injuring hundreds on Oct. 1, 2017.
Nov. 5, 2017: Sutherland Springs, Texas
Incident date: Nov. 5, 2017 City/county: Sutherland Springs, Texas Killed: 25
A law enforcement official walks past the First Baptist Church of Sutherland Springs, the scene of a mass shooting, Sunday, Nov. 5, 2017, in Sutherland Springs, Texas.
Feb. 14, 2018: Parkland, Florida
Incident date: Feb. 14, 2018 City/county: Parkland, Florida Killed: 17
Parents wait for news after a reports of a shooting that killed 17 at Marjory Stoneman Douglas High School in Parkland, Fla., on Wednesday, Feb. 14, 2018.
May 18, 2018: Santa Fe, Texas
Incident date: May 18, 2018 City/county: Santa Fe, Texas Killed: 10
People react outside the unification center at the Alamo Gym, following a shooting at Santa Fe High School Friday, May 18, 2018, in Santa Fe, Texas.
Oct. 27, 2018: Pittsburgh, Pennsylvania
Incident date: Oct. 27, 2018 City/county: Pittsburgh, Pennsylvania Killed: 11
Students from the Yeshiva School in the Squirrel Hill neighborhood of Pittsburgh, pay their respects as the funeral procession for Dr. Jerry Rabinowitz passes their school en route to Homewood Cemetery following a funeral service at the Jewish Community Center, Tuesday Oct. 30, 2018.
Nov. 7, 2018: Thousand Oaks, California
Incident date: Nov. 7, 2018 City/county: Thousand Oaks, California Killed: 12
In this image taken from video a victim is treated near the scene of a shooting, Wednesday evening, Nov. 7, 2018, in Thousand Oaks, Calif. A hooded gunman dressed entirely in black opened fire on a crowd at a country dance bar holding a weekly "college night" in Southern California, killing multiple people and sending hundreds fleeing including some who used barstools to break windows and escape, authorities said Thursday. The gunman was later found dead at the scene.
May 31, 2019: Virginia Beach, Virginia
Incident date: May 31, 2019 City/county: Virginia Beach, Virginia Killed: 12
A police chaplain heads toward Princess Anne Middle School in Virginia Beach, Va, on Friday, May 31, 2019. A longtime city employee opened fire at a municipal building in Virginia Beach, killing 11 people before police shot and killed him, authorities said. Six other people were wounded in the shooting, including a police officer whose bulletproof vest saved his life, said Virginia Beach Police Chief James Cervera.
Aug. 3, 2019: El Paso, Texas
Incident date: Aug. 3, 2019 City/county: El Paso, Texas Killed: 23
An El Paso police officer talks to a store employee following a shooting at a shopping mall in El Paso, Texas, on Saturday, Aug. 3, 2019. Multiple people were killed and one person was in custody after a shooter went on a rampage at a shopping mall, police in the Texas border town of El Paso said.
Aug. 4, 2019: Dayton, Ohio
Incident date: Aug. 4, 2019 City/county: Dayton, Ohio Killed: 9
Shoes are piled outside the scene of a mass shooting at Ned Peppers bar, Sunday, Aug. 4, 2019, in Dayton, Ohio. Nine people in Ohio were killed in the second mass shooting in the U.S. in less than 24 hours.
Aug. 31, 2019: Midland, Texas
Incident date: Aug. 31, 2019 City/county: Midland, Texas Killed: 7
Law enforcement officials process the crime scene from a shooting which ended with the shooter being shot dead by police in a stolen mail van, right, in Odessa, Texas. The mass shooting in West Texas spread terror over more than 10 miles as the gunman fired from behind the wheel of a car.
March 16, 2021: Atlanta
Incident date: March 16, 2021 City/county: Atlanta, Georgia Killed: 8
Law enforcement officials confer outside a massage parlor following a shooting on Tuesday, March 16, 2021, in Atlanta. Shootings at two massage parlors in Atlanta and one in the suburbs left eight people dead, several of them women of Asian descent, authorities said Tuesday.
March 22, 2021: Boulder, Colorado
Incident date: March 22, 2021 City/county: Boulder, Colorado Killed: 10
Police work on the scene outside a King Soopers grocery store where gunman killed 10 people on Monday, March 22, 2021, in Boulder, Colo.
April 15, 2021: Indianapolis
Incident date: April 15, 2021 City/county: Indianapolis Killed: 9
Police stand near the scene where multiple people were shot at the FedEx Ground facility early Friday morning, April 16, 2021, in Indianapolis. A gunman killed eight people and wounded several others before apparently taking his own life in a late-night attack at a FedEx facility near the Indianapolis airport, police said.
May 14, 2022: Buffalo, New York
Incident date: May 14, 2022 City/county: Buffalo, New York Killed: 10
People pray outside the scene of a shooting where police are responding at a supermarket, in Buffalo, N.Y., May 15, 2022. When police confronted Payton Gendron, the white man suspected of killing 10 Black people at the supermarket, he had an AR-15-style rifle and was cloaked in body armor. (AP Photo/Matt Rourke, File)
May 24, 2022: Uvalde, Texas
Incident date: May 24, 2022 City/county: Uvalde, Texas Killed: 21
A visitor places bracelets on crosses at a memorial as he and others pay their respects to the victims killed in the Robb Elementary School shooting, Tuesday, May 31, 2022, in Uvalde, Texas. (AP Photo/Eric Gay)