A man who went on a deadly shooting, carjacking and robbery rampage in California's Central Valley died Monday during a high-speed highway chase during which he intentionally tried to smash into other cars, authorities said.

Gustavo Garcia, 36, of Visalia was pronounced dead at the scene Monday morning on State Route 65 in Porterville after he was flung from a stolen truck after a gun battle with police and wrong-way car crashes that left four people injured, one critically, police said.

In attacks on apparently random strangers, Garcia also killed a man at a gas station convenience store, shot and wounded a farmworker in an orchard and a woman at a motel, carjacked other farmworkers and robbed a convenience store at gunpoint, Tulare County Sheriff Mike Boudreaux said.

He also fired shots in the backyard of his ex-girlfriend's Visalia home as she and her children were inside and may have committed as many as a dozen crimes during a 'rampage' that began Sunday afternoon, he said.

Gustavo Garcia, 36, of Visalia was pronounced dead at the scene Monday morning on State Route 65 in Porterville after he was flung from a stolen truck after a gun battle with police and wrong-way car crashes that left four people injured, one critically, police said

Shortly before 1:30am Monday, Garcia fired shots into a Shell gas station in the Pixley area, then about an hour later, he killed Rocky Paul Jones (pictured), 51, of Visalia outside the Arco AMPM in that city, Visalia Police Chief Jason Salazar said

What remains of one of the vehicles involved in the crash on State Route 65 in Porterville, California is seen above on Monday morning

'We have one man that essentially (has) been on a personal reign of terror,' Boudreaux said at an afternoon news conference.

Authorities were 'scratching our heads' about a motive but Garcia may have been distraught over some relationship breakup, the sheriff said.

An autopsy would determine whether he had any drugs or alcohol in his system.

Garcia had a long criminal history that included arrests for drugs, assault with a deadly weapon, vandalism and contributing to the delinquency of a minor and he had been in trouble with immigration officials several times and was deported in 2014, Boudreaux said.

However, he did not know Garcia's recent immigration status.

The rampage began around 1pm Sunday in Exeter when Garcia shot a farmworker who was picking fruit, police said.

He was expected to recover.

Minutes later, Garcia robbed a convenience store.

Surveillance video showed Garcia firing shots at the ceiling and demanding more than $2,000 in cash, the Fresno Bee reported.

At least four cars were involved in a crash as Garcia led police on a 100mph high speed chase

Garcia was flung from his stolen truck after he was driving the wrong way along the highway

Garcia died after smashing into four cars, leaving one driver in critical condition and the other three with minor injuries

A second man who had been a passenger in Garcia's car was being sought as a person of interest in the holdup, police said.

At about 7:30pm Sunday, Garcia shot a Motel 6 guest in the arm and chest in Tulare, although her wounds weren't life-threatening, authorities said.

'She had made eye contact with the subject and he had followed her to her parking spot, where he got out of the car and for an unbeknownst reason began firing at her vehicle,' Tulare interim Police Chief Matt Machado said.

Shortly before 1:30am Monday, Garcia fired shots into a Shell gas station in the Pixley area, then about an hour later, he killed Rocky Paul Jones, 51, of Visalia outside the Arco AMPM in that city, Visalia Police Chief Jason Salazar said.

Jones had exchanged words with Garcia before the shooting but it was unclear whether Jones had any relationship with the killer, police said.

'It appears his rampage and his acts of violence were random and they were not chosen targets, which makes it even more dangerous,' Boudreaux said.

'This person was targeting anyone who got in the way.'

Garcia later went to his ex-girlfriend's house in Visalia and fired several shots from her backyard but she and her children escaped unharmed, police said.

He then fired shots into a home in the Sultana area, then shortly after 6:30am crashed his car after a two-minute police chase during which he shot and hit pursuing sheriff's cars and deputies fired back.

Garcia ran into an orchard where he stole a truck at gunpoint from three farmworkers and led authorities in a chase that reached 100 mph on State Route 65, where Garcia drove the wrong way in traffic and seemed intent on trying to hit other cars, California Highway Patrol Lt. Scott Goddard said.

Garcia died after smashing into four cars, leaving one driver in critical condition and the other three with minor injuries, Goddard said.

He 'had no regard for human life,' Boudreaux said.