(NewsNation) —  After a recent string of shootings that claimed the lives of three homeless men in Los Angeles, authorities announced the arrest of 33-year-old suspect Jerrid Joseph Powell on Saturday.

The arrest also links Powell to a separate killing in a follow-home robbery in San Dimas, according to Los Angeles Police Chief Michel Moore. 

During an afternoon news conference attended by Mayor Karen Bass and District Attorney George Gascón, Moore revealed that Powell is believed to be responsible for the series of shootings that occurred over the past week.

Authorities arrested Powell on Wednesday but waited to announced on Saturday.

The arrest followed closely on the heels of city officials’ announcement, less than 24 hours prior, that a killer was specifically targeting the unhoused. 

Moore said that each victim was shot while asleep or in the process of lying down. Powell was responsible for four murders in four days.

Powell was apprehended after a traffic stop in Beverly Hills on Wednesday. Police identified Powell’s vehicle, leading to the recovery of the weapon used in the crimes and subsequent arrest by Beverly Hills Police Department officers. 

“Over the course of the investigation of our murders, we were able to identify the vehicle we believe is connected to our three homicides as being the same vehicle that Mr. Powell used in the murder of Mr. Simbolon,” Moore said at Saturday’s press conference. “[We learned] that it was being held in custody of the Los Angeles County Sheriff’s Department as evidence of their murder.”

Los Angeles County Sheriff Robert Luna explained that detectives, suspecting the vehicle’s involvement in a previous murder, entered its license plate number into an automatic license plate reader system. This action led to the Beverly Hills officers conducting the crucial traffic stop. 

“We know there’s controversy out there about the usage of this system,” Luna said, “but let me tell our community something. If we did not enter that plate into the system, this individual that we believe is responsible for at least four murders may have [still] been out there and reoffended.” 

Bass expressed gratitude for the collaboration among various government agencies to ensure the safety of the unhoused population.

“Twenty-four hours ago, we announced there was a killer on the loose; now he is in custody,” Bass stated.

Powell now faces murder and robbery charges in connection with the follow-home murder in San Dimas.

From Nov. 26 through Nov. 29, three men were found dead, all under similar circumstances.

“A single individual approached each one and shot and killed each one as they slept,” Moore said.

Each of the three killings happened in the early morning, all before 5 a.m.

The first happened on Nov. 26, around 3:10 a.m. near the intersection of 110th Street and Vermont Avenue in the Westmont neighborhood.

The second happened the following day in downtown Los Angeles on the 600 block of Mateo Street. Police discovered that victim around 4:45 a.m.

The most recent known killing happened on Nov. 29 around 2:30 a.m. near the intersection of N. Avenue 18 and Pasadena Avenue in Lincoln Heights.

Though the police chief declined to use the term “serial killer,” Bass was slightly more forceful in her description of the murders.

“I want to be very clear about what we’re facing today: This is a killer who is preying on the unhoused,” Bass said, adding that homeless people should not sleep alone.

Bass encouraged any friends or relatives of homeless people to reach out and warn them of the danger and encourage them to sleep at a shelter and not alone in an isolated area. She also promised to the city’s most vulnerable citizens that justice would come.

“To the person responsible: We will find you, we will catch you and you will be held accountable,” Bass said.

“An assault on one of us is an assault on all of us,” Gascón added.

A task force had been set up to solve these murders Moore previously said.

Police also encouraged unhoused citizens to make sure their cell phones are charged and in working condition and to record or take note of any suspicious activity.

Powell is a convicted felon and acquired the weapon illegally.

NewsNation’s affiliate KTLA contributed to this report.