Alleged gunman's first words after mass shooting at supermarket

Disturbing new details have emerged about a mass shooting in the small Colorado city of Boulder that has yet again rocked the US.

Ahmad Al Aliwi Alissa, 21, has been charged with 10 counts of murder in connection with the deadly attack at a grocery store but his motive remains unclear, US authorities say.

Police said he was in a stable condition after suffering a leg wound in an exchange of gunfire with responding police officers at the King Soopers outlet in Boulder, about 45km northwest of Denver, on Monday afternoon.

The 10 victims, whose names were released at a Tuesday morning news conference, range in age from 20 to 65 and include Eric Talley, an 11-year veteran of the Boulder police force and dad of seven.

A police affidavit revealed Alissa purchased a Ruger AR-556 semiautomatic pistol just six days before the deadly shooting. It is unclear if the weapon was used in the attack.

He was known to the FBI for his links to another person under investigation, officials revealed.

Shooter's first words to police

Immediately following his arrest, Alissa refused to answer questions, however made a request to speak to family.

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

The document revealed grisly details of his alleged actions during the shooting. It states Alissa shot an elderly man in the supermarket's car park before walking up to him, standing over him and shooting him several more times.

He had stripped off all his clothing bar a pair of shorts, including a green tactical vest.

Dramatic helicopter footage showed Alissa being apprehended by police as blood poured from his leg wound.

Another video shot by one of the people in the store showed several bodies lying motionless in the car park as the man called for others to call 911.

Police officer's wish before tragic death

Talley, 51, was the father of seven children and had recently been looking for a less dangerous job, according to a statement released by his father.

He was discovered by SWAT members with a gunshot wound to the head.

Boulder Police Chief Maris Herold described his death as "tragic". She said he had seven children aged between five and 18.

"He loved this community. And he was everything that policing deserves and needs. He cared about this community.

“He was willing to die to protect others.”

Residents paid tribute to Talley by placing flowers on and surrounding his police vehicle outside Boulder Police station.

Police identified the nine other victims as Denny Strong, 20; Neven Stanisic, 23; Rikky Olds, 25; Tralona Bartkowiak, 49; Suzanne Fountain, 59; Teri Leiker, 51; Kevin Mahoney, 61; Lynn Murray, 62; and Jody Waters, 65.

Second mass shooting in the US in just a week

The bloodshed marked the country's second mass shooting in a week.

A gunman went on a killing spree on March 16 in the Atlanta area, fatally shooting eight people at three day spas before he was arrested.

Investigators said they were confident Alissa had acted alone although they did not offer any details on what might have motivated the massacre.

"It would be premature for us to draw any conclusions at this time," Michael Schneider, the agent in charge of the FBI's field office in Denver, said at a news briefing.

Alissa was later released from the hospital on Tuesday and transported to jail to await an initial court appearance, officials said.

Monday's attack, which began about 2.40pm, drew hundreds of police officers to the scene and sent terrified shoppers and employees fleeing for safety amid the sound of gunfire.

The shooting added to the Rocky Mountain state's tragic list of mass killings that include 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.

"My heart aches today," Governor Jared Polis said on Tuesday.

"Flags had barely been raised back to full-mast after the tragic shooting in Atlanta that claimed eight lives, and now a tragedy here close to home at a grocery store that could be any of our neighbourhood grocery stores."

President Joe Biden said he was "devastated" by the shooting and called on Congress not to “wait another minute” to push through legislation to ban assault rifles.

With Reuters

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