(BOULDER, Colo.) — The man accused of killing 10 grocery shoppers in Boulder, Colorado, in March 2021 entered a plea of not guilty by reason of insanity on Tuesday.

According to detectives, Ahmad Al Aliwi Alissa, 24, was ordered back to the Colorado Mental Health Institute and will be evaluated by January 8, 2024, ahead of a scheduled trial in August.

A Boulder police detective at Tuesday’s preliminary hearing described the events of the mass shooting in disturbing detail as observers in the courtroom cried silently.

During the shooting, Alissa allegedly moved quickly from the parking lot and through the aisles of the King Soopers grocery store chasing and shooting at customers with an AR-15-style rifle as they ran and hid from the gunfire.

Boulder police detective Sarah Canty testified that all but one of the deceased victims were shot multiple times. At least two victims were shot at close range, as they hid under or between pieces of store equipment.

The criminal proceedings against Alissa, who suffers from schizophrenia, have been repeatedly postponed while he was found to be mentally incompetent to stand trial, however that decision was reversed in October. Detectives say they have yet to establish a clear and specific motive for the shooting.

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