The hunt for Shareef Allman of San Jose began after authorities said he opened fire at a routine safety meeting at Permanente Quarry around 4:15 a.m. and later wounded a woman in a failed carjacking.
Schools were closed or on lockdown in Cupertino, home of Apple Inc., and in neighboring communities as authorities went door to door with guns drawn and residents were warned to stay indoors.
Meanwhile, friends and neighbors expressed disbelief and sadness at the possibility the man they knew as an outgoing, engaged member of the community could have committed such horrific acts of violence.
Allman became upset and left the meeting then returned with a handgun and rifle and started shooting people, Santa Clara County sheriff's Lt. Rick Sung said. About 15 workers were at the meeting during the shooting, which authorities said lasted about two minutes.
Sheriff Laurie Smith said two people were pronounced dead at Permanente Quarry in the foothills outside Cupertino, and a third person died later at a hospital.
Six others at the quarry were wounded and taken to hospitals, where some remained in critical condition, Smith said.
The names of the victims have not been released.
Relatives of victims and other employees rushed to the quarry to check on their loved ones. One woman, who asked to remain anonymous because the gunman was still at large, said her father worked at the quarry for about 10 years and was the lead employee on the night shift.
She said he called his family around 4:30 a.m. to say something was happening and not to pick him up. He called again just after 6 a.m. to say he was OK but was hiding.
He called a third time to say he was coming out of hiding.
Later in the day, authorities located Allman's vehicle and seized a shotgun, a handgun and two rifles believed to belong to the suspect, Smith said, adding that some of the weapons were found in the car.
"The challenges are the big geographical area," she said of the manhunt. "The challenges are that he's armed."
Around 7 a.m., authorities received a 911 call that a woman was shot in an attempted carjacking near Hewlett-Packard Co.'s Cupertino campus by a man matching Allman's description. The shooter fled on foot after using a weapon similar to a gun used in the quarry shooting, authorities said.
The carjacking victim, a Hewlett-Packard contract employee, was in fair condition at Santa Clara Valley Medical Center, according to hospital spokeswoman Joy Alexiou. Another victim was treated and released from the hospital, while a third remained in fair condition, she said.
Allman was last seen in surveillance footage from a nearby gas station shortly after the shooting outside Hewlett-Packard, Smith said. In the video, he appeared to be armed, she said.
The shootings rattled those who know Allman.
"He's always had a smile on his face," said Paulette Conner, 57, a neighbor at Allman's San Jose apartment complex who said she's known him for five years. "I've never known him to have any violent tendencies. Never. Ever."
Conner said Allman occasionally griped to her and others over the years about his job, including his various shift changes and some co-workers.
Allman is known as a local fixture long involved in San Jose's black community. Before a news conference where community leaders urged him to turn himself in, friends described Allman as a non-violent person not known to own guns.
"He used to do so much for the community. Something must have happened to make him flip out like this," said Pastor Oscar Dace of Bible Way Christian Center. "Everybody just can't believe that this has happened."
Police said Allman is 47, though California voter registration records put his age at 49.
In addition to working at the quarry, Allman once ran a nonprofit group for youths, wrote a novel titled "Amazing Grace" that sought to empower women against domestic violence, and produced and hosted a public access television show for CreaTV in San Jose.
Suzanne St. John-Crane, executive director of CreaTV, said she had spoken with him numerous times but did not know him well.
"Based on what we know now, we're shocked and devastated and feel for the families of the victims," St. John-Crane told The Associated Press. "But he didn't work here. I want to make that clear. We're very frightened."
A video posted on YouTube shows Allman interviewing the Rev. Jesse Jackson outside a memorial for the late musician Walter Hawkins for a piece for CreaTV. In the video, Allman talks with Jackson about the positive and transformative messages of gospel music
"I hope what he gave all of us we take out to our community and use it to better ourselves and our community," Allman said about Hawkins during the interview.
Business records show that in 2004, Allman started a youth development organization called Helping Hands Changing Hearts, which listed its location as Allman's home address. However, the IRS automatically revoked the organization's exempt status as a nonprofit for failure to file proper tax forms for three consecutive years, records showed.
The Permanente Quarry is a limestone and aggregate mining operation and cement plant owned by Lehigh Southwest Cement.
"Our thoughts and prayers are with the victims and their families," Dan Harrington, president and chief executive of parent company Lehigh Hanson Inc., said in a statement. "I have committed the company's resources to assist our affected employees during this difficult time."
The quarry was issued its first permit in May 1939, according to Santa Clara County documents.
The site has been subject to a number of environmental violations over the years, and has been subject to noise and other complaints from nearby residents.
Lehigh makes about 1.2 million tons of cement a year, and its products are involved in a number of major construction projects including the seismic upgrades off the Golden Gate Bridge.
Associated Press writers Jason Dearen, Terry Collins, Sudhin Thanawala, Marcus Wohlsen and Beth Duff-Brown and photographer Paul Sakuma contributed to this report.