George Holliday, the plumber who videotaped White Los Angeles police officers beating Black motorist Rodney King in 1991, capturing a brutal attack that became a symbol of racial injustice and helped spark a week of deadly riots after the officers were acquitted, died Sept. 19 at a hospital in Simi Valley, Calif. He was 61.

The cause was complications of covid-19, said his friend Robert Wollenweber. Mr. Holliday had been hospitalized with the coronavirus for about a month.

Shot in grainy black and white, the video of King’s beating was played and replayed on hundreds of television stations, seared into the national consciousness as the police officers went on trial and parts of Los Angeles went up in flames. The video was an early example of the power of citizen journalism, in which a bystander with a camcorder or cellphone could document a historic event that might otherwise be overlooked.

It was also one of the first videos to capture an act of police brutality, specifically against an unarmed Black man, and expose it to a wide audience. “The Rodney King video was the Jackie Robinson of police videos,” the Rev. Al Sharpton told the New York Times last year. In June, the Pulitzer Prize board awarded a special citation to another citizen journalist, Darnella Frazier, whose cellphone footage of George Floyd’s murder sparked a national reckoning over racial justice and police misconduct.

Mr. Holliday said he had no grand intentions when he picked up his new Sony Handycam on the early morning of March 3, 1991. He had been awakened around 12:45 a.m. by police sirens and a low-flying helicopter and went out on his apartment balcony in Lake View Terrace to see what was happening, bulky camera in hand. “You know how it is when you have a new piece of technology,” he later told the Times. “You film anything and everything.”

As he looked through the viewfinder, Mr. Holliday saw King forced to the ground, where police kicked him, shot him with Tasers and beat him with batons, breaking his cheekbone, skull bones and ankle. “It felt like I was an inch from death,” King later said. The attack followed an eight-mile chase in which King, who had been drinking and was on parole for a robbery conviction, tried to avoid being stopped for speeding.

Mr. Holliday, who grew up in Argentina, recalled wondering what the man could have done to deserve such an attack. “I came from a different culture, where people would get disappeared with no due process,” he said in a video interview. “Police would pick people up on suspicion. I didn’t expect this in the U.S.” He went back to sleep, then filmed a friend running the Los Angeles Marathon and went to a wedding with his wife.

But the next day, he called the police to find out what had happened. When they declined to share information, he rang the local news station KTLA. Its journalists found out he had filmed the beating, asked to see the tape and then interviewed Mr. Holliday at his home. “We were all shocked by it and realized from the first that it was important,” KTLA news director Warren Cereghino later told The Washington Post.

What followed was a media firestorm, with KTLA’s story on the attack prompting similar segments across the country. The footage fueled a nationwide examination of police brutality as four of the officers went on trial. On April 29, 1992, a predominantly White jury acquitted three of the men of assault charges. A mistrial was declared for the fourth. “Viewed from outside the trial, it was hard to understand how the verdict could possibly square with the video,” President George H.W. Bush said in a nationally televised address.

Within hours of the verdict, violence and looting erupted in Los Angeles. More than 50 people died during the riots, with an estimated $1 billion of damage done to the city. Mr. Holliday said he received death threats, with some people blaming him for the violence. “If my tape hadn’t been there, I think something else would have triggered it,” he told the Los Angeles Times in 1996.

The four police officers were indicted on federal civil rights charges, with two found guilty and sentenced to two years in prison. King, who died in 2012 at age 47, was awarded $3.8 million in damages.

Mr. Holliday said he met King only once, when King called his name at a gas station, about a year after the riots. “I looked over and I didn’t recognize him because the only pictures I had seen of him were of his face all swollen and beaten up, but now he’d recovered,” Mr. Holliday told the British tabloid the Sun. “He could tell that I didn’t know who he was and he said, ‘You don’t know who I am, do you?’ I said, ‘No.’

“He said, ‘Well, you saved my life.’ ”

Mr. Holliday occasionally discussed his own life with journalists, saying that his mother was German and his father was a British executive at Shell oil. His job caused the family to move frequently: Mr. Holliday was born in Canada, lived in Indonesia and spent most of his childhood in Argentina before coming to Los Angeles around 1980 in search of work.

One of his grandfathers had been a police officer in London. “I always had — and I still do have — a high opinion of the police,” he told the Sun in March. “I think they’re given a very bad rap, one they don’t deserve. They do a lot of good things and you never see anybody talk about that stuff.”

Mr. Holliday said he bought his Sony Handycam as a Valentine’s Day gift for his first wife, Maria. Before filming King, he shot footage of Arnold Schwarzenegger acting in a scene from “Terminator 2: Judgment Day” at a bar across the street from his home.

He was later twice divorced, according to a 2006 account in the Los Angeles Times, and scraped by as a self-employed plumber. He said that while he never filmed the police beating to make money, he felt used by TV stations that broadcast his footage while giving him little credit and no compensation. By his account, he received $500 from KTLA, but no more than a few thousand dollars in all for licensing the video.

Survivors include his wife, Sandra; a son, George; four stepchildren; a brother; and a sister, according to a statement from his representative Roby Massarotto.

The original King tape was confiscated by law enforcement while the beating was being investigated, and Mr. Holliday tried unsuccessfully to get it back. The FBI did eventually return his Sony Handycam, which he tried to auction last year for $225,000. He told the New York Times he hoped the auction would “inspire people to use their cameras for everything, the bad and the good.”

“People can accuse other people of doing stuff,” he added. “But when it’s on camera, it’s different. You just can’t argue with it.”

Mr. Holliday had hoped to buy a home with the auction money, but he had no bidders, according to the Sun. “I’ve been a plumber for 43 years,” he said. “It looks like I’m going to have to be a plumber for quite a few more years.”