This article is more than 1 year old

This article is more than 1 year old

Authorities in southern California are searching for answers after a brutal and apparently random series of stabbings left four dead and two others wounded.

A 33-year-old man from the city of Garden Grove allegedly carried out the violent attacks and robberies on local businesses during the two-hour wave of violence on Wednesday, police said.

The violence, which took place at multiple locations in Garden Grove and the neighboring city of Santa Ana, appeared to be random and the only known motives seem to be “robbery, hate, homicide”, Lt Carl Whitney of Garden Grove police told reporters on Wednesday. “We know this guy was full of anger and he harmed a lot of people tonight.”

The brutal and puzzling attack came just days after a pair of mass shootings in Texas and Ohio left 31 people dead and stunned the nation.

The suspect was arrested as he walked out of a convenience store in Santa Ana, dropping a knife and a gun he had taken from a security guard he had just killed.

The attacker and four of the victims were described as Hispanic, while two victims were described as Caucasian, police said in a statement. Initially, all had been described as Hispanic.

The two people who were wounded were listed in stable condition on Wednesday night and were expected to survive.

One of the dead was identified by his son as Helmuth Hauprich, 62, a hard-working immigrant originally from Romania who came to the US more than two decades ago.

Facebook Twitter Pinterest This photo provided by Erwin Hauprich shows Erwin Hauprich and his father, Helmuth Hauprich, right, who was killed in Thursday’s attacks. Photograph: AP

In a telephone interview with the Associated Press, Erwin Hauprich described his father as a down-to-earth man who strove to make a life for his family.

Erwin Hauprich said his father called him on Wednesday afternoon and told him his Garden Grove apartment had been burglarized. The father said his passport, green card, sword collection and even a dining table were taken.

Erwin Hauprich said his father never called back and he went to check on him after hearing there had been a stabbing at the complex. A police officer told him that Helmuth Hauprich had been taken to the hospital, where he died, the son said. He said he was told his father’s roommate was killed in the apartment.

On Thursday morning police had blocked off the roads to the two-story apartment complex in the city of Garden Grove, known as Casa de Portola, where the stabbing occurred.

Whitney said a nearby bakery was also robbed. The owner, who asked not to be identified, told KCAL-TV that she was charging her cellphone at about 4pm when the man drove up and apparently mistook her for a customer.

“He went directly to the register and tried to open the register … he showed me a gun,” she said. He took all the money and fled.

“I think I was very lucky because he thought I was a customer, not the owner,” she said.

The man also robbed an insurance business, where a 54-year-old employee was stabbed several times and was expected to survive. He was armed with “some sort of machete knives” when he confronted the woman, Whitney said.

The woman “was very brave”, Whitney said. “She fought as best she could.”

An alarm company saw the robbery on a live television feed and called police.

“They could see that the female victim was on the ground with blood and multiple injuries,” Whitney said.

The man fled with cash and also robbed a check-cashing business next door, the lieutenant said.

Shortly after 6pm, the attacker drove up to a Chevron station, where he attacked a man pumping gas “for no reason”, Whitney said. “There was no robbery.”

The man was stabbed in the back and “his nose was nearly severed off his face”, the lieutenant said. Bystanders rushed to help the man, he said.

Undercover detectives tracked the suspect’s silver Mercedes to the parking lot of the 7-Eleven store in Santa Ana and within a minute the man emerged from the store, carrying a large knife and a gun that he had cut from the belt of a security guard after stabbing him, Whitney said.

The man had followed the guard into the store and stabbed him several times during a confrontation, Whitney said.

Police ordered the man to drop his weapons and he complied and was arrested.

Police then learned that a male employee of a nearby Subway restaurant had also been fatally stabbed during a robbery, Whitney said.