BOULDER, Colo. (AP) — The father of a mentally ill man who killed 10 people at a Colorado supermarket testified Tuesday at his murder trial that he thought his son may have been possessed by an evil spirit before the attack.

Sometime before the attack in Boulder in 2021, Moustafa Alissa recalled waking up in the middle of the night to use the bathroom and his son, Ahmad Alissa, telling him to go talk to a man who was in his room. Moustafa Alissa said they walked together to his son's room and there was no one there.

Moustafa Alissa also said his son would sometimes talk to himself and broke a car key fob he feared was being used to track him, echoing testimony on Monday from his wife. He said he didn't know exactly what was wrong with his son but that in his native Syria people say someone acting that way is believed to be possessed by an evil spirit, or djin.

“We thought he probably was just possessed by a spirit or something,” Moustafa Alissa said through an Arabic interpreter in court.

Ahmad Alissa was diagnosed after the shooting with a severe case of schizophrenia and only was deemed mentally competent to stand trial last year after a doctor put him on the strongest antipsychotic medication available. No one disputes he was the gunman at the supermarket but he has pleaded not guilty by reason of insanity.

The defense says he should be found not guilty because he was legally insane and not able to tell the difference between right and wrong at the time of the shooting.

Prosecutors and forensic psychologists who evaluated him for the court say that, despite his mental illness, he did not experience delusions and knew what he was doing when he launched the attack. They point to the planning and research he did to prepare for it and his fear that he could end up in jail afterward to show that Alissa knew what he was doing was wrong. However, the psychologists said they thought the voices played some role in the attack and don't believe the attack would have happened if he had not been mentally ill.

When District Attorney Michael Dougherty asked why Moustafa Alissa did not seek out treatment for his son, he said it would be very hard for his family to have a reputation for having a “crazy son.”

"It’s shameful in our culture," he said.

During questioning, Moustafa Alissa, whose family owns several restaurants in the Denver area, also acknowledged that Ahmad Alissa had promised to return a gun he had that had jammed a few days before the shooting and that he went to the shooting range at least once with his brothers. Despite his concerns about his son's mental state, he said he did not do anything to try take guns away from him.

Given that, Dougherty suggested that his son's condition may not have been as bad as his family is now portraying it.

“He was not normal but we did not expect him to do what he did,” Moustafa Alissa said.