BOULDER: The 21-year-old suspect in this week's Colorado mass shooting will make his first court appearance on Thursday (Mar 25), three days after authorities say he opened fire at a supermarket and killed 10 people, including a policeman.
Ahmad Al Aliwi Alissa faces 10 counts of murder and an attempted murder charge stemming from the rampage on Monday at King Soopers grocery store in the Table Mesa section of Boulder, about 45km northwest of Denver. He will appear in county court in Boulder at 8.15am, according to court records.
The massacre was the country's second mass shooting in a week, after another gunman shot eight people to death at three Atlanta-area day spas on Mar 16.
The twin attacks prompted President Joe Biden to call on Congress to strengthen gun restrictions. Legislation to bolster background checks and ban certain semi-automatic rifles has stalled amid Republican opposition.
Police have not yet publicly identified a motive for the killings. Alissa's 34-year-old brother described him as antisocial and paranoid in an interview with the Daily Beast.
The suspect's sister-in-law told police on Monday evening that he had been "playing with" a firearm she described as resembling a "machine gun" two days earlier, upsetting family members, according to an arrest affidavit filed by police in the case.
The gunman arrived at the King Soopers store armed with an AR-style semi-automatic rifle and a handgun and wearing a tactical vest, according to the affidavit.
The affidavit also said law enforcement databases show that six days earlier Alissa purchased a Ruger AR-556 pistol, a weapon that resembles a semi-automatic rifle.
Alissa, a naturalised US citizen from Syria who graduated from Arvada West High School in 2018, pleaded guilty to third-degree assault for punching a classmate in late 2017.
The classmate said the attack was unprovoked, an account supported by interviews with several witnesses, according to an Arvada Police Department incident report. Alissa told an officer the classmate had called him a "terrorist" and racist names.
Alissa was sentenced to probation and community service.
The 10 victims on Monday included Eric Talley, an 11-year veteran of the Boulder police force who was among the first officers on the scene. Talley, 51, was a father of seven who had been looking for less dangerous work, according to his father.
Also killed were Denny Stong, 20; Neven Stanisic, 23; Rikki Olds, 25; Tralona Bartkowiak, 49; Suzanne Fountain, 59; Teri Leiker, 51; Kevin Mahoney, 61; Lynn Murray, 62; and Jody Waters, 65. Stong, Olds and Leiker worked at the store.
Witnesses told police the assailant killed one man in his vehicle and then gunned down another in the parking lot. The shooter stood over him, firing multiple times, before entering the store to continue the rampage.
When apprehended, Alissa did not answer questions but asked to speak with his mother, according to the affidavit.
Makeshift memorials of flowers, votive candles and condolence messages sprang up this week outside the supermarket and at police headquarters.
Colorado has seen some of the most shocking episodes of gun violence in US history, including the 2012 mass shooting at a movie theatre in Aurora and the 1999 rampage at Columbine High School, near Littleton.