Updated:

The 21-year-old suspect in Monday’s massacre at a Colorado supermarket — which left 10 dead including a store manager and a police officer — faces 10 counts of murder in the first degree, police said Tuesday. Ahmad Al Aliwi Alissa, of Arvada is the 21-year-old suspect of Monday’s massacre in Colardo. Alissa is accused of 10 counts of murder from opening fire on Monday afternoon at the King Soopers Grocery store in Boulder, Colorado, killing people ranging in age from 20 to 65.

Colorado authorities responded to reports of a potential active shooter at a supermarket on Monday.

Police said there were multiple victims of the incident but did not reveal if those casualties were fatalities or injuries. A suspect allegedly opened fire on responding officers in the parking area. They believe the individual had a long gun in his possession.

Colorado Shooter

Later, two police officers were seen escorting a handcuffed, shirtless man with blood running down his leg out of the store. Authorities later uploaded a post on Twitter saying there was a shooter at a King Soopers grocery store.

Video footage from a helicopter camera showed police cars and officers gathering outside the grocery store with SWAT teams and at least three helicopters on the building’s roof. Officers could be seen drawing their guns, some of whom were stationed at broken windows.

Police used a loudspeaker to warn the suspect they had the building surrounded and that “you need to surrender.” They advised the man to come out with his hands in the air and unarmed.

One witness who was shopping at the store said he first heard a loud bang, followed by two more, causing others to flee. He said he and a few others ran back into the back of the store where employees helped them escape.

An ambulance was later seen going away from the store, allegedly carrying the bleeding man who was escorted by police. Officers were seen assisting residents left inside the grocery store out to safety.

“I am closely watching unfolding events at King Soopers in Boulder. My prayers are with our fellow Coloradans in this time of sadness and grief as we learn more about the extent of the tragedy,” Colorado Governor Jared Polis said in a Twitter post, 6ABC reported.

Owner of Under the Sun Eatery and Pizzeria Restaurant, Kevin Daly, said he was just one block away from the grocery store when he saw police cars rushing to the scene and shoppers fleeing the building. He helped shelter several people looking for safety and said others got on a bus provided by Boulder police.