(CNN) -- A manhunt was under way Wednesday for a man suspected of killing three people and wounding seven others, some critically, in a workplace shooting in Cupertino, California, and of a subsequent attempted carjacking nearby.
Police identified the suspect as Shareff Allman and said he is about 45 years old. However, CNN affiliate KGO reported the man's first name was spelled Shareef.
The shooting occurred about 4:15 a.m. (7:15 a.m. ET) at the Permanente Quarry, said Santa Clara County Sheriff Laurie Smith. Authorities believe Allman entered a meeting, armed with a handgun and an assault rifle, and opened fire.
Two people died at the scene, Smith said, and a third was pronounced dead later at a hospital.
According to Santa Clara County sheriff's Sgt. Jose Cardoza, witnesses reported the incident lasted "no more than two minutes."
At about 7 a.m. (10 a.m. ET), Allman was believed to be involved in an attempted carjacking on the Hewlett-Packard campus in Cupertino, about five miles away from the quarry, Smith said. A woman was shot and sustained non-life-threatening injuries. The suspect did not obtain the woman's car, the sheriff said. He is believed to have fled on foot.
Cardoza said earlier the weapon used in the attempted carjacking was a handgun similar to that used in the workplace shooting.
Authorities found Allman's vehicle at a service station close to the site of the attempted carjacking, Smith said. Police recovered a shotgun, a handgun and two assault rifles, she said.
Residents of the area in suburban San Jose have been alerted that a suspect is at large, Smith said. Many schools in the area were closed and Cupertino's emergency operations center was activated.
Allman is believed to be armed and dangerous, Smith said. She described him as a "disgruntled employee" of the quarry.
He has a "minor criminal record," the sheriff said, with the latest incident in 1996. Authorities have been in touch with Allman's family, she said.
KGO reported that Allman is a community television host who regularly preaches about non-violence.
Hewlett-Packard asked employees at the Cupertino campus not to report to work Wednesday, KGO reported. HP said in a statement the woman injured in the attempted carjacking was an HP contract employee and was in stable condition at a hospital, the station said.
The Santa Clara County government describes the Permanente Quarry as "a limestone and aggregate mining operation in the Santa Clara County foothills."
CNN's Ninette Sosa contributed to this report.