UVALDE, Texas -- Alleged school shooter Salvador Ramos was in the classroom for 77 minutes before officers entered and killed him, ABC News reported.
During that time, he discharged 315 rounds of ammunition, with hundreds of those rounds fired within the first four minutes of his arrival, authorities said.
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After the initial barrage, the police commander on the scene mistakenly believed the shooter was barricaded and it was no longer an active shooter incident, Texas Department of Public Safety Director Steve McCraw told reporters in an update Friday. But as officers gathered outside the classroom, the gunman kept shooting on at least six occasions, the new details show.
At 11:35 a.m., as the first three officers entered the building and approached classrooms 111 and 112, the suspect fired into the hallway through a closed door, where two officers sustained "grazing wounds," McCraw said.
He fired an additional 16 rounds two minutes later -- at 11:37 a.m. -- and again at 11:38 a.m., 11:40 a.m. and 11:44 a.m., according to McCraw, who did not specify whether the additional discharges were directed at officers in the hallway or at those inside the classrooms.
At 12:21 p.m., with as many as 19 officers then gathered outside the classroom, the suspect again fired at the closed door, forcing officers to "move down the hallway," McCraw said.
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Despite those additional spurts of gunfire - and a 911 call from inside one of the classrooms alerting a dispatcher that eight or nine people remained alive -- officers did not enter the classroom and kill Ramos until 12:50 p.m., according to McCraw.
The police response to the shooting is now being investigated, Texas Gov. Greg Abbott said Friday.