FRESNO, Calif. (KFSN) -- A girlfriend could play a big role in proving if a Squaw Valley man is the serial killer prosecutors claim he is.
Buford King is accused of murdering three men between 2011 and 2016, but he wasn't charged until 2019.
Squaw Valley buzzed with news of disappearances in 2016 - first, Aleksey Shelest in May and then Donnie Lee in November.
Three years later, Lee's girlfriend got an unexpected visit and an ominous apology from Buford King's girlfriend.
"Basically had told her she's sorry for her loss - referring to Donnie Lee - and that information was going to be coming out to basically give the families some closure," said Det. Jose Diaz of the Fresno County Sheriff's Office.
Within days, detectives dug up King's backyard and a neighbor's and discovered two bodies.
They had surveyed the property three years earlier, but didn't find anything.
This time around, though, they had help from King's girlfriend, who said she witnessed several acts of domestic violence and child abuse by King.
"She had said that she was scared of Mr. King," Det. Diaz said. "She was afraid Mr. King was going to kill her."
King was in jail for allegedly shooting someone in the foot when she came forward.
She told them she heard a gunshot in November and then King came in and said he wanted to show her something near the back of their five-acre property.
"She saw Donnie Lee laying on the ground and she stated there was something covering Donnie Lee's head," Det. Diaz said.
Investigators found Lee and Shelest's bodies in Squaw Valley.
Someone had shot each of them in the head.
Detectives also got tipped off to go to Tulare County, where they found the remains of Albert Contreras, who disappeared in 2011.
Detectives went to jail to interview King.
They showed the 36-year-old Iraq War veteran photos of the dug-up victims and asked what he knew.
"Alex was killed for molesting that little boy," Det. Diaz said.
Detectives say King confessed to all three killings.
His attorney hasn't said what approach the defense will take, but he challenged whether detectives legally obtained King's confession.
A judge is expected to decide Tuesday whether there's enough evidence for King to stand trial for the murders.
After that, prosecutors are expected to decide whether to pursue the death penalty against King by the time he makes his next court appearance.