Prosecutors plan to charge a Los Angeles man in connection with three murders across Southern California, calling the suspect a “stone-cold serial killer,” as part of a deadly robbery crime spree last week at a half-dozen 7-Elevens and a doughnut shop.

Investigators have linked Malik Patt, 20, to the fatal shooting of a homeless man in Los Angeles on July 9, as well as the July 11 deaths of a 7-Eleven clerk in Brea and a man who intervened in a robbery in a 7-Eleven parking lot in Santa Ana.

Three other peop le were shot and wounded in the July 11 violence, one of whom remained gravely injured Monday, according to Orange County District Attorney Todd Spitzer.

Patt faces a slew of charges, including murder, attempted murder, robbery and carjacking. If convicted, his case could result in the death penalty or a life sentence without the possibility of parole.

“Malik Patt is a stone-cold serial killer,” Spitzer said Monday in a news conference announcing the planned filing of criminal charges. “There’s no other way to describe him. He executed innocent people and shot others.”

The July 11 robberies occurred within five hours in San Bernardino, Orange and Riverside counties, setting off an intensive manhunt that resulted in the arrests of the two men in Los Angeles on Friday. Authorities say Jason Payne, 44, was Patt’s neighbor and accomplice but was not involved in the killings.

Both men are being held in jail and are expected to be arraigned Tuesday. It was not immediately clear whether they had attorneys who could speak on their behalf.

Spitzer called the violence among the “cruelest, most inhumane crimes I’ve ever seen” in his time in law enforcement.

Police originally believed the spate of robberies at the convenience stories on July 11, or 7/11, might be linked to the day when the national 7-Eleven brand celebrates its anniversary. It was the chain’s 95th year, and stores gave out free Slurpee drinks.

But Spitzer on Monday said that while investigators are still looking into the potential nexus, “it appears it might be random and coincidental.”

Matthew Hirsch, a 40-year-old clerk, was shot and killed at the Brea store, and Matthew Rule, 24, was shot and killed in the parking lot of the Santa Ana store while trying to intervene in the robbery of someone else. The identify of the homeless man who was slain in Los Angeles has not been made public.

Detectives also believe Patt may be connected to other crimes, including robberies in the San Fernando Valley.

(AP)