TUSTIN, Calif. (AP) -- A young man shot a woman to death in a home early Tuesday then went on a spree of carjackings and random shootings across Orange County that left two more people dead and three others wounded before the gunman killed himself, authorities said.
Many more victims were shot at but unhurt, Tustin Lt. Paul Garaven said.
The gunman was only described as being in his 20s, and his motive was not known, according to officials of at least four agencies investigating multiple crime scenes.
It was unclear if the victims knew each other or the shooter, Orange County sheriff's spokesman Jim Amormino said.
"It might have been a random thing," he said. "We just don't know."
The shootings began at 4:45 a.m. when deputies responding to a call found the woman shot multiple times in a house in Ladera Ranch, about 55 miles southeast of Los Angeles.
Several shootings occurred in the next hour at other locations.
One involved a carjacking at Interstate 5 and Red Hill Avenue. Police said the victim was uninjured, but an innocent bystander was hit by gunfire and taken to a hospital.
Reports indicated the gunman also opened fire at other vehicles on a freeway.
Later, a pickup truck taken by the carjacker began to run out of gas, so he stopped at State Route 55 and McFadden Avenue in Santa Ana, city police Cpl. Anthony Bertagna said.
"He gets out of the vehicle, confronts our victim who is in his BMW, he orders him out of the vehicle, walks him to the side of the curb and executes our victim," Bertagna said.
The shooter then drove to a Tustin business called Micro Center. A utility-type pickup was carjacked, one person was killed, and another wounded, Garaven said.
Officers located the suspect and followed him into the city of Orange.
When officers tried to stop him, he got out of the vehicle and killed himself, Garaven said. A shotgun was recovered at the scene.
Authorities did not have details about all the victims.
"There have been other people coming forward saying they were shot at or their cars were shot at," Garaven said but none had reported any serious injuries.
Of the wounded, two were described as having serious injuries and one was said to be minor.
The southbound 55 McFadden Avenue off-ramp was closed until further notice.
Tustin is about 35 miles southeast of downtown Los Angeles.
Associated Press Writer Sue Manning in Los Angeles contributed to this report.
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