Santa Clara County Sheriff's Sgt. Jose Cardoza said the man was shot and killed around 7:30 a.m. Thursday in Sunnyvale.
Several media outlets earlier reported that the man who was shot was 47-year-old Shareef Allman, but Cardoza told The Associated Press he can't confirm that.
The shooting took place in a residential neighborhood about 5 miles east of Permanente Quarry, where Allman allegedly opened fire on his co-workers a day earlier. Three people died, and six were wounded.
Authorities believe Allman also shot a woman in an attempted carjacking about an hour after fleeing the quarry. Thursday's encounter with law enforcement took place about a block from that carjacking, near Hewlett-Packard Co.'s Cupertino campus.
Cardoza didn't immediately provide details on how the suspect shooting unfolded.
Hours after the fatal confrontation, the man's body covered by tarp remained in the driveway of a home, and authorities cordoned off the streets surrounding the scene.
Jenny Martin, who lives nearby, said authorities had scoured neighborhood Wednesday in search of Allman.
"We were in the house lockdown all day yesterday," Martin said. "We've never seen anything like it in our neighborhood."
"The SWAT stormed in like ninjas, and they took a position in our front bedroom," she said.
According to authorities, Allman became upset Wednesday during a safety meeting at Permanente Quarry. Allman left the meeting and returned with a handgun and rifle and started shooting people, Santa Clara County sheriff's Lt. Rick Sung. About 15 workers were at the meeting.
Santa Clara County Sheriff Laurie Smith identified the dead as Manuel Pinon, 48, of Newman, Calif., and John Vallejos, 51 and Mark Munoz, 59, both of San Jose. Six others at the quarry were wounded and taken to hospitals, where some remained in critical condition, Smith said.
Later Wednesday morning, authorities received a 911 call reporting an attempted carjacking 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. She said a quarry shooting victim was listed there in good condition Thursday, and another victim was treated and released shortly after the shooting.
Schools were locked down in Cupertino, home of Apple Inc., and in nearby communities as authorities went door to door with guns drawn and residents were warned to stay indoors.
Authorities found Allman's car, and collected 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 shootings rattled those close to Allman.
To his friends, Allman was the big man with a big smile, a devoted single father of two who once worked tirelessly to raise money for Hurricane Katrina victims, and who penned a novel about the evils of domestic violence.
"He was always helping people," said Walter Wilson, a community activist who has known Allman all his life. He said he last saw Allman three weeks ago at downtown music festival, where he seemed happy and jovial. "He spent his life in the service of other people. This is totally out of character for him.
Allman would attend every one of his daughter's basketball games, or any event she was in.
"You talk about Mr. Mom," said Sandra Dailey, 54, who described herself as a close friend. "He never missed an event. He was an incredible father."
In addition to working at the quarry, Allman has run a nonprofit group for youths and produced and hosted a public access television show for CreaTV in San Jose.
He also wrote a novel titled "Saving Grace," about the evils of domestic violence.
On the back cover of the book, Allman wrote a poem and included a statement that the book is not a reflection of himself, but of "man's inhumanity."
"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."