Minnesota shooting: 911 audio reveals response | LiveNOW from FOX

Emergency dispatch audio reveals what happened when first responders were called to a Minneapolis school after police say a lone shooter opened fire on a crowd of people as they prayed inside the church.

The first calls for medical teams were dispatched to the Annunciation Catholic School and Church in South Minneapolis around 8:30 a.m. Wednesday.

"Minneapolis has a possible active shooter," one first responder said.

Troopers arriving at the scene were advised of the need for immediate medical help.

"Bring all the gauze that you have," said another first responder.

Medical teams said that there were "two DOAs inside the church."

Minneapolis Police Chief Brian O’Hara confirmed that two young children – ages 8 and 10 – were killed as they sat in the pews of the church. Police say the shooter opened fire through a church window, firing off dozens of rounds.

One dispatch call said, "We have… two patients with gunshot wounds to their heads in front. There’s also a critical patient in the rear of the church."

Authorities say 17 victims were injured, most of them children.

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