A bench warrant of $500,000 has been issued for Hawaii State Hospital escapee Randall Saito, who was acquitted of the 1979 murder of Sandra Yamashiro by reason of insanity. Getty Images/ Dan Kitwood

A bench warrant of $500,000 has been issued for Hawaii State Hospital escapee Randall Saito, who has also been charged with felony escape. Saito escaped from the facility Sunday, then reportedly took a charter plane to Maui, before boarding a Hawaiian Airlines flight to San Jose, California.

Saito, 59, was acquitted of the 1979 murder of Sandra Yamashiro, 29, at Ala Moana Center by reason of insanity. He was diagnosed with sexual sadism and necrophilia, which is a sexual attraction to corpses.

Yamashiro was shot in the face by a pellet gun and then stabbed to death, according to Hawaii News Now. Due to the gruesome nature of the crime, prosecutors had opposed the acquittal at the time, arguing, "The defendant committed a cold-blooded murder."

On the other hand, Saito’s lawyer David Schutter asked for his client to be remanded in the Hawaii State Hospital for a long time.

Schutter said, “I think Randall Saito will be in the state mental hospital or whatever facility they assign him for a long, long time, and by long, long time I’m referring to long after my death,” FOX affiliate Khon2 reported.

This is not the first time Saito attempted to get out of the hospital. In 1993, he appeared in front of the court to demand he be allowed to walk out of the hospital as he was no longer a threat to the community.

Psychologist Marvin Acklin testified at the time, backing up the claims made by the defense.

“Based on my psychological evaluation of Mr. Saito that the report which I wrote was based on, it was not my opinion at that time that he represented an imminent danger to himself or to others,” Acklin said.

However, the prosecutor begged to differ, pointing out that Saito had not lost his killer instincts.

“Randall Saito is a very disturbed, mentally ill individual,” Deputy Prosecutor Jeff Albert said. “He’s a very dangerous individual with respect to whom all the predictors indicate that if he were to be released, he would kill again.”

Saito’s plea was ultimately squashed by a Circuit Court judge. His case was reviewed again in 2015, when Deputy Prosecutor Wayne Tashima presented the argument concluding he was still too dangerous to be let out of the hospital premises for any reason whatsoever.

One of the reasons Saito’s demand was denied multiple times was because he was called a master manipulator by people who have interacted with him. An unnamed medical staffer, who had contact with Saito inside the Hawaii State Hospital vouched for his manipulative nature.

"They'll never find him," said the staffer. "He's a smart guy. He's not impulsive. It's not an impulsive act. He had some planning. He had someone on the outside."

The staffer also added Saito was a psychopath who was unable of feeling empathy toward anyone. Also, there were no improvements in Saito’s mental condition because he repeatedly refused psycho-therapy while in the hospital.

Following his escape, Hawaii Attorney General Doug Chin's office has charged Saito with escape in the second degree, a class C felony with a maximum sentence of 5 years in prison and a $10,000 fine, ABC affiliate KITV reported. Chin has branded Saito “a dangerous individual. We need him off the streets. The State is in close contact with law enforcement to make this happen.”