Joseph Naso, 77, was arrested Monday by Marin County detectives following his release from the El Dorado County jail, where he had been in custody over the past year on unrelated charges, Marin County District Attorney Ed Berberian told reporters.
He is eligible for the death penalty.
But an oddity in the victims' names, matching initials, also has investigators in New York wondering if Naso is responsible for the so-called "double initial" murders in that state.
Three girls murdered in upstate New York in the early 1970s all had matching initials for their first and last names, as did the four California victims.
Naso's arraignment is scheduled for Wednesday afternoon, Berberian said, and he will be presented with a criminal complaint at the hearing.
Investigators indicated that they found evidence during a random probation search of Naso's Reno, Nevada, home last year that linked him to the four killings California.
A separate task force is looking into whether any other cold cases in the U.S. can be linked to Naso, a professional photographer who often traveled the country for work and may have killed in other states, Nevada law enforcement officials said at a news conference Tuesday.
Naso's arraignment is scheduled for Wednesday afternoon, Berberian said, and he will be presented with a criminal complaint at the hearing. He was being held without bail in the Marin County Jail on Tuesday, Berberian said.