Uvalde surveillance footage shows police response as gunman murdered 19 children and 2 adults

Portions of surveillance footage of the Robb Elementary School shooting were published by the Austin American-Statesman and KVUE on Tuesday ahead of a planned release by officials on Sunday. 

The footage shows the gunman, who authorities have identified as 18-year-old Salvador Ramos, firing multiple shots from an AR-15 style rifle outside the school, then entering the building at 11:33 a.m. and shooting his way into adjoining classrooms. 

A barrage of more than 100 bullets were fired inside those two classrooms over the next two-and-a-half minutes before seven officers ran into the school at 11:36, two of them armed with rifles and four others armed with handguns. 

Officers were on the scene before the gunman entered the school, as one officer had the suspect in his rifle sights and asked permission to shoot, but the supervisor either didn't hear the request or didn't respond in time, allowing the suspect to enter the school, according to a report released by the Advanced Law Enforcement Rapid Response Training Center.