BOULDER, Colo. (AP) — Authorities in Colorado responded to what they said was an active shooter at a supermarket Monday.

It's unclear if anyone has been injured, but a shirtless man with blood running down his leg was escorted out of the store in handcuffs by two police officers.

Police in Boulder tweeted Monday that the shooter is at a King Soopers grocery store.

Television helicopter video showed law enforcement vehicles and officers massing outside, including SWAT teams, and at least three helicopters on the roof of the store in the southern part of the city of Boulder.

Officers had their guns drawn outside, and some windows at the front of the store were broken.

An ambulance pulled away from the store, apparently carrying the bleeding man brought out of the store in handcuffs.

TV footage showed officers helping two people to safety.

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