BOISE -- Experts will have more time to decide whether a man accused of stabbing a 3-year-old girl to death at her own birthday party in Boise this summer is mentally fit to stand trial for her murder.

Timmy Kinner, 30, is charged with killing little Ruya Kadir and stabbing eight other people - five of them children - as they celebrated at the Wylie Street Station Apartments June 30.

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Lawyers for Kinner have previously said the suspect suffers from "mental conditions" that impair his decision-making abilities. But Judge Nancy Baskin said during a Tuesday hearing that a psychologist who evaluated Kinner was not able to determine whether or not he is competent to stand trial.

Prosecutors announced last week that they will seek the death penalty if Kinner is convicted of Ruya's murder.

Police have previously said that Kinner did not know any of the victims, all of whom were refugees from Syria, Ethiopia and Iraq. The suspect, who had come to Boise from California not long before the attack, had briefly stayed with another resident of the apartment complex, but had been asked to move out.

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According to investigators, Kinner returned to the complex looking for his former housemate, but after learning that person was not home, turned his attention to the birthday party.

A family member of several of the victims said Kinner plunged his knife into a child being carried in its mother's arms, than stabbed the woman repeatedly as she tried to shield her child.

Several children crammed into a closet and dialed 911 as the carnage unfolded outside.

Prosecutors say other children and adults who tried to stop the attack were slashed across the face, stabbed in the stomach or chest, and suffered injuries including broken bones and knocked-out teeth.

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Ruya, who was the most seriously wounded in the attack, was airlifted to a hospital in Salt Lake City, but did not survive.

Kinner was taken into custody by police at the scene; the large folding knife used in the attack was fished from a nearby canal.

The suspect's defense team have not elaborated on what mental conditions they believe Kinner is afflicted with, and it's not clear whether he has been formally diagnosed with any mental illness. Judge Nancy Baskin barred journalists and other members of the public from the courtroom for about 20 minutes as she discussed Kinner's medical information with the attorneys.

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Dr. Chad Sombke, the psychologist appointed by the court to evaluate Kinner, reported that the suspect refused to cooperate with the evaluation on Sept. 19. Later, on Oct. 17, Sombke was able to test Kinner for about 45 minutes, but ultimately could not draw a conclusion about his mental fitness.

Baskin ruled an independent psychiatrist will next attempt to discern whether Kinner can stand trial in the case.

Idaho law does not allow for an "insanity defense," and Kinner would not walk free if he is deemed incompetent to stand trial.

The law does require that a defendant be able to understand what is happening in court and assist their lawyers in their own defense. If a suspect cannot do that, they are typically sent to either the state hospital or the Idaho Department of Correction.

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If the defendant - through medication, mental health treatment or other means - ever reaches the point where evaluators believe their competency is restored, the case against them would be scheduled for trial.

Kinner's next hearing is set for Dec. 13.