Kenneth Rasmuson, previously convicted of abducting and sexually assaulting a 3-year-old boy, pleaded not guilty Wednesday to charges that he molested and killed a boy in 1986.
Rasmuson, 53, is charged with two counts of murder in the deaths of two 6-year-old boys, Jeffrey Vargo and Miguel Antero, according to the Los Angeles County district attorney's office. It is also alleged that he performed lewd or lascivious acts.
The boys' deaths remained unsolved for many years until DNA evidence recently linked Rasmuson to their killings, officials said.
Rasmuson plead guilty to Jeffrey's death in July. His plea on Wednesday comes after detectives announced last week new DNA evidence connecting Rasmuson to Miguel.
Rasmuson was arrested at his parents' home in Idaho in March in connection with Jeffrey's death. Jeffrey disappeared on July 2, 1981, when he left his home in Anaheim Hills to go look at a fireworks stand. The next day, two construction workers found his body in Pomona.
In April 1986, Miguel disappeared just outside his home after hopping off a school bus. His body -- covered in stab wounds -- was found amid brush in Agoura Hills hours later.
At the time, detectives weren't able to connect Rasmuson to the boys' deaths.
A year after Miguel was killed, Rasmuson kidnapped a 3-year-old boy from a home near downtown Los Angeles and sexually abused him. The boy was abandoned naked in a remote area in Agoura and was found by a passerby.
With his parents by his side, Rasmuson, then 25, surrendered to Los Angeles police days later. He pleaded guilty and was sentenced to 17 years in prison for kidnapping and molestation.
At the sentencing, a prosecutor called Rasmuson "an unrepentant child molester."
Rasmuson had a history of abuse.
In 1982, Rasmuson was declared a mentally disordered sex offender for sodomizing an 11-year-old Santa Barbara boy. He was committed to Atascadero State Hospital in Central California and released after two years.
Times staff writer Matt Hamilton contributed to this report.
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