911 tapes of Navy Yard shooting

The 52-minute recording of the emergency response to the shooting at Washington Navy Yard sounds like the soundtrack of a disaster movie. But this time, the action is real.

In the recording of 911 exchanges, calm voices recount the events of Monday morning when a lone gunman, identified as Aaron Alexis, entered the Naval Sea Systems Command headquarters inside the yard.

According to the FBI, Alexis was armed with a shotgun and obtained a handgun inside the building. He killed 12 people before he was shot to death by authorities.

PHOTOS: At the scene of Navy Yard shooting

“Man on the fourth floor, multiple shots fired, multiple people down,” says the dispatcher in a calm voice that belies that unfolding horror:

Alexis enters the massive Building 197, where 3,000 or so people work, about 8:15 a.m. He opens fire with the shotgun into a glass-walled cafeteria where employees are eating breakfast.

Authorities respond within minutes of the first 911 call and Alexis shoots at them as well.

“We have a report on the fourth floor, a male with a shotgun, multiple shots fired, multiple people down,” the recording goes on. “We’re still waiting for the OK that the scene has been secured,” an ambulance crew member says on emergency transmissions posted on Broadcastify.com, a source of live public safety audio feeds.

More bulletins follow: “Shooter known to be in the main gate area.... Officer down on the third floor.... Female on the roof, shot in the shoulder.”

Alexis takes a handgun from an officer and, armed with two weapons, terrorizes the building’s occupants.

“Clear the area, clear the area,” comes the official response.

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