A screenshot of web streaming shows the King Soopers supermarket in the city of Boulder, Colorado, the United States. Ten people were killed in the mass shooting at the supermarket on March 22, 2021.(Photo: Xinhua)

 
A 21-year-old man was charged with 10 counts of first-degree murder in connection with Monday's mass shooting in a supermarket in U.S. state of Colorado, authorities said Tuesday.

The suspect was identified as Ahmad Al Aliwi Alissa, said Maris Herold, police chief of Boulder, at a news conference. Ten people, including one police officer, were killed in the mass shooting at the King Soopers supermarket in the city of Boulder.

Officials said the shooter, undergoing treatment at a hospital, is a resident in the nearby city of Arvada.

Monday's live video from local TV stations showed a shirtless man with blood on his leg was taken out of the supermarket in handcuffs by three police officers.

Among the ten victims, Eric Talley, 51, was the first officer to arrive at the store and was killed by the suspect.

"Rest In peace Officer Eric Talley. Your service will never be forgotten," the Boulder Police Department lamented on Twitter.

The other nine victims have been identified by authorities as Denny Strong, 20; Neven Stanisic, 23; Rikki Olds, 25; Talona Bartkowiak, 49; Suzanne Fountain, 59; Teri Leiker, 51; Kevin Mahoney, 61; Lynn Murray, 62; and Jody Waters, 65.