Jerrid Joseph Powell, 33, is accused of targeting men sleeping alone on the street in three locations.

He was arrested last week over the robbery and fatal shooting of a homeowner in his garage.

Mr Powell is reportedly charged with four murders, and was expected to appear in court on Monday.

"It was chilling and I've been in this work for four-plus decades," Los Angeles police chief Michael Moore said on Saturday. He called the killings "senseless".

Over the span of four days, authorities allege, Mr Powell targeted some of the city's most vulnerable residents in apparently random attacks.

The killings began in the early hours of 26 November, when Jose Bolanos, 37, was fatally shot in an alley as he slept on a couch.

About 24 hours later, 62-year-old Mark Diggs was pushing a cart in a neighbourhood near downtown Los Angeles when he was gunned down.

The following Wednesday, a homeless Latino man was fatally shot in the early hours of the morning. Police have not named him as his family had yet to be notified.

By last Friday, Los Angeles' police chief and Mayor Karen Bass were warning of a potential serial killer targeting the city's homeless.

Mr Powell was arrested on Wednesday night in Beverly Hills, initially in relation to another murder a day earlier.

Police said they had linked his car to the shooting of 42-year-old father-of-two Nicholas Simbolon in a suspected 'follow-home' robbery at his residence in the Los Angeles suburb of San Dimas.

According to the Los Angeles Times, Mr Powell fled the scene in a 2024 BMW M440i, which he owns.

Authorities used a controversial licence plate scanning technology to identify the vehicle in Beverly Hills.

The tools have raised privacy concerns, but Los Angeles authorities defended the system, saying it allowed them to prevent further harm.

Mr Moore, the LAPD police chief, said they believed the car was linked to the killings of the three homeless men. He also said a handgun that police seized during Mr Powell's arrest was "positively identified" as the murder weapon in the deaths of all three homeless men.

Mr Powell is being held on $2m bail.

There are about 170,000 homeless people in California, of whom around 46,000 live in the city of Los Angeles, according to a June survey by the Los Angeles Homeless Services Authority.

The Los Angeles killings are the latest episode of violence against homeless people.

In November, prosecutors in Orange County, California, charged a man with manslaughter over the death of a homeless man who had been sleeping on the pavement.

On Friday, an unknown gunman opened fire at a homeless encampment in Las Vegas, Nevada, killing one person and seriously injuring three others. Police have yet to identify a suspect.

By Kayla Epstein