BREAKING: Suspect arrested in killings of 4 people in LA area, including 3 homeless

Announcement of Joseph Powell's arrest on Saturday, came after he was arrested last Thursday after he allegedly robbed a home and killed a man in a residential neighborhood in San Dimas, NBC News reports. Police Chief Michel Moore said that they used surveillance footage to identify Powell in the murder of the three homeless men and that a handgun found in the truck matched the weapon used.

The announcement comes one day after Los Angeles Mayor Karen Bass put out a statement urging homeless individuals to seek shelter and warned the suspect that "We will find you, we will catch you, and you will be held accountable."

According to Fox 11, "A handgun recovered from Powell’s vehicle following Simbolon’s murder was used in the three homeless killings, said LAPD Chief Michel Moore. Powell’s vehicle was also present at all four crime scenes, according to authorities."

On Tuesday, Simbolon, who worked as a project manager in the Los Angeles County executive office, was found by his wife inside his Tesla in the garage of the home, suffering from a gunshot to the upper body, according to witnesses and sheriff’s officials. Paramedics pronounced him dead at the scene.

Authorities said all three victims were shot in the same manner and the shooter is believed to have acted alone. One was killed on a couch in an alley, another was shot sleeping on a sidewalk, and the other had been stopped while pushing a shopping cart.

In the Friday press brief, Moore said, "We don't know what the motive is on this, except we know that the targeting is three individuals, sleeping alone, that were houseless."

Police did not release the charges that Powel faces in Saturday's press brief.