BOULDER, Colo. (CBS4) — The suspect in the mass shooting at a grocery store in Boulder on Monday has been identified as 21-year-old Ahmad Al Aliwi Alissa (also known as Ahmad Al-Issa) from Arvada. He was led out of the store in handcuffs, wearing nothing but shorts.

(credit: Boulder Police)

Ten people, including one police officer, were killed at the King Soopers store at Table Mesa Drive and South Broadway.

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“The suspect has been identified as a Ahmad Alissa, 21 of Arvada, he has been charged with 10 counts of murder in the first degree,” said Boulder Police Chief Maris Herold.

Alissa bought the weapon on March 16, just six days before the attack.

According to the arrest affidavit, eyewitnesses said they saw a man wearing body armor or tactical gear shoot a man in the parking lot.

One witness said the shooter “walked up to the elderly man, stood over him and shot him multiple additional times.”

He then entered the store and continued shooting.

One 911 caller described the shooter as a “white male, middle-aged with dark hair, a beard, a black vest, and a short-sleeved shirt.”

The gunman was inside with the victims for approximately 40 minutes before an officer shot him in the leg and took him into custody.

Police say Al-Issa removed all his gear inside the store, which included a green tactical vest, a rifle, possibly an AR-15, a semiautomatic handgun, a pair of jeans and a dark-colored long-sleeved shirt.

The SWAT team walked him out of the store and put him in an ambulance. Blood was visible on his right leg and foot.

(credit: CBS)

According to the affidavit, the suspect did not answer questions, “though he asked to speak to his mother.”

Officers did not observe the odor of alcoholic beverage on his breath and said there was no indication of impairment due to drug use. He told paramedics he was not using any medications

There is no information about a possible motive at this time. Investigators believe there are no other suspects involved in the shooting.

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He was booked into the Boulder County Jail after being released from the hospital.

According to two law enforcement officials, Alissa was born in Syria in 1999, emigrated to the U.S. as a toddler and later became a U.S. citizen, the Associated Press reported. He would need to be a citizen to buy a gun.

Alissa attended Arvada West High School beginning in March 2015 until he graduated in May 2018, officials confirmed.

According to police records, his only previous criminal history is a charge for third-degree assault out of Arvada in 2018.

On Monday, investigators who searched the suspect’s home, where he lives with his brother in Arvada, spoke to a woman who identified herself as his sister-in-law. She told police it the suspect was seen playing with a gun she thought looked like a “machine gun” about two days ago. She said she thought he still had access to the gun.

In a phone interview with The Daily Beast, the suspect’s older brother described him as paranoid and “very anti-social.”

He told the outlet he was sure the shooting was “not at all a political statement, it’s mental illness.”

Damien Cruz says he was a friend of the suspect.

“He talked about how Muslims were all treated horribly. They weren’t treated equally as everybody else. Just because how their names were spelled, they were putting a frame on him that he was ISIS. Just because of how his name is spelled and where he’s from that’s not right. And I could see where he was coming from, but I just don’t know why he would choose this way to get his point across,” Cruz told CNN.

On his Facebook page, Alissa wrote of “trying to make the world a better place.”

Two law enforcement sources said investigators are looking at the possibility that mental illness was a significant factor in the violent rampage, including paranoia, which appears to have intensified in recent months.

The source cautioned that the investigation is ongoing, but the two sources said there is nothing at this point to indicate the suspect Ahmad Al Aliwi Alissa had been radicalized or that ideology played a role in the shooting spree.

When he appeared for his first court hearing on Thursday, Alissa was in a wheelchair, pushed by a police officer. He was wearing blue scrubs and a while face mask.

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(credit: CBS)

Alissa did not get up during the brief hearing. He looked around and seemed alert but did not speak.

(credit: CBS)

Anica Padilla