A Phoenix man accused of sexually attacking and fatally stabbing two young women in separate killings 30 years ago, one of whom was decapitated, was convicted Tuesday of all charges including murder.

Bryan Patrick Miller waived his right to a jury trial, so Maricopa County Superior Court Judge Suzanne Cohen decided his fate.

The Maricopa County Attorney’s Office said Tuesday in a statement that the court would now move into the aggravation phase of the trial but did not elaborate.

He faced two counts each of first-degree murder, kidnapping and attempted sexual assault.

Miller, 50, never testified during the trial, which began in October. He initially used an insanity defense.

PHOENIX THEFT SUSPECT DIES AT HOSPITAL WHILE IN POLICE CUSTODY

He was accused of killing Angela Brosso in November 1992 on the eve of her 22nd birthday and 17-year-old Melanie Bernas in September 1993.

Brosso and Bernas both disappeared while riding their bicycles along the Arizona Canal in north Phoenix, according to authorities.

A man has been found guilty in the slayings of two women along a Phoenix canal.

Police believe the killer knocked Brosso off her bicycle, stabbed her and dragged her off the trail. Her naked body was found decapitated near a bike trail.

Ten months later Bernas’ body was discovered floating in the canal. Police said she was not decapitated. Her bicycle was missing.

Authorities said DNA evidence showed the attacks were linked to the same suspect, and Miller was arrested for the killings in January 2015.

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Prosecutors filed a notice of intent to seek the death penalty for Miller that same year.

According to police, Miller denied any involvement although he acknowledged living in the vicinity of the killings at the time and said he rode his bike on paths in the area.

It took years before Miller was found mentally competent to stand trial.