BOULDER, Colo. (AP) — A mentally ill man who killed 10 people at a Colorado supermarket told psychologists he heard “killing voices” right before opening fire, a psychologist testified Friday during the gunman’s trial.

Ahmad Al Aliwi Alissa, who has been diagnosed with a severe case of schizophrenia, repeatedly failed during about six hours of interviews to provide any more details about the voices or whether he heard them saying anything other than that they were yelling, forensic psychologist B. Thomas Gray said.

“I started hearing voices, like killing, like killing voices,” Alissa said in one portion of the videotaped interviews shown in court. The clips showed Alissa fidgeting, yawning and stretching at times and speaking in a soft voice that was often difficult to hear over a hum on the recordings.

After the interviews, Gray and fellow forensic psychologist Loandra Torres determined that at the time of the 2021 shooting in the college town of Boulder, Alissa was legally sane — able to understand the difference between right and wrong.

No one, including Alissa’s lawyers, disputes he was the shooter. Alissa has pleaded not guilty by reason of insanity in the shooting. The defense says he should be found not guilty because he was insane and not able to tell the difference between right and wrong at the time of the shooting.

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In questioning Gray, one of Alissa’s attorneys, Kathryn Herold, pointed out that Gray and Torres did not have full confidence in their finding, largely because Alissa did not provide them more information about what he was experiencing even though that could have helped his case. She noted they were relying on a man with treatment-resistant schizophrenia experiencing hallucinations to explain what was happening to him.

Alissa also said he was planning to die in the attack so he would not have to go to jail, Gray said. Herold pointed out that Alissa surrendered instead. Alissa stripped down to his underwear before he was arrested in the store, apparently to show he was no longer armed and not a threat.

Alissa is charged with 10 counts of first-degree murder, multiple counts of attempted murder and other offenses, including having six high-capacity ammunition magazine devices banned in Colorado after previous mass shootings.

Testimony on Alissa’s sanity is expected to wrap up Monday. The defense will then start to present its case, which is set to include calling Alissa’s relatives as witnesses.