SACRAMENTO, Calif.  — A DNA match led to the arrest of a 72-year-old former police officer in one of the most baffling and sadistic crime sprees of the 1970s and ‘80s — a string of at least 12 slayings and 45 rapes in California by an attacker dubbed the Golden State Killer, police said Wednesday.

Armed with a gun, the masked attacker would break into homes while single women or couples were sleeping. He sometimes tied up the man and piled dishes on his back, then raped the woman while threatening to kill them both if the dishes tumbled. He often took souvenirs, notably coins and jewelry, from his victims, who ranged in age from 13 to 41.

The match led to Joseph James DeAngelo, who was fired in 1979 from the police department in Auburn, northeast of Sacramento. Despite an outpouring of thousands of tips over the years, his name had not been on authorities’ radar before last week, District Attorney Anne Marie Schubert said.