The head of the Texas Department of Public Safety on Friday said police officers made the "wrong decision, period" to not enter the Uvalde classroom sooner, as they waited in the hallway and children called 911, asking for police to help.
Texas DPS executive director Steven McCraw, in a news conference Friday morning, said there were 19 police officers inside the school but they did not breach the door for about an hour.
As they waited, one child who had called 911 asked dispatch to "please send the police now."
McCraw said the commanding officer at the scene viewed the situation as a barricaded suspect and that they were waiting for more equipment to arrive to breach the classroom door.
But McCraw said, in hindsight, that was the wrong decision.
"When there's an active shooter, the rules change," McCraw said. "It's no longer a barricaded subject. You don't have time.
McCraw's acknowledgment that police at the scene made a wrong decision comes as authorities have faced intense scrutiny and criticism over how they responded to the shooting at Robb Elementary School, where 19 students and two staffers were killed.
McCraw was pressed several times by reporters on why officers did not enter the classroom sooner, despite responding to the school within minutes of the first shots being fired.
"There's no excuse for that," McCraw said. "I wasn't there, but from what we know, we believe this should have been an entry as soon as possible."
McCraw on Friday also gave a more detailed timeline of how the shooting unfolded -- from when the shooter shot his grandmother at her home to when he was killed inside the classroom by Border Patrol agents -- and he read details from 911 calls placed inside the school.
Watch McCraw's full news conference here:
Watch McCraw explain the timeline that led up to the shooting and when it began:
How the shooting unfolded
McCraw gave a similar timeline Friday to the one given by Victor Escalon, a regional director of Texas DPS, on Thursday, but with more details.
In new information revealed by McCraw, the door the shooter, Salvador Ramos, entered at Robb Elementary had been propped open by a teacher just one minute before Ramos crashed a pickup truck near the school.
The door was propped open at 11:27 a.m.; Ramos crashed at 11:28 a.m.
The same teacher then ran to a classroom to get a phone and then went back to the open door.
Shortly after Ramos crashed, he shot at two men who were near a funeral home across from the school. As the shooting happened, the teacher who was at the open school door went back inside and began calling 911, McCraw said.
The 911 call was placed at 11:30 a.m., reporting there was a crash and a man with a gun.
One minute later, Ramos arrived outside the school and began shooting toward classrooms, firing up to 100 rounds.
As he shot at the school, responding officers went to the nearby funeral home, near where Ramos crashed and shot at the two men.
One of the responding officers from the school district drove past Ramos, who was hunkered down behind a vehicle, McCraw said.
At 11:33 a.m., Ramos entered the school through the door that was propped open. He began shooting into a classroom, firing more than 100 rounds, according to audio evidence, McCraw said.
Here is a replica map of how the shooter entered the school:
At 11:35 a.m., three Uvalde police officers entered the building, McCraw said. They were joined by four other officers.
The three initial officers who arrived went to the closed classroom door and were grazed by gunfire.
More gunfire was heard from inside the classroom at 11:37 a.m., 11:38 a.m., 11:40 a.m. and 11:44 a.m., McCraw said.
At 11:51 a.m., more police and federal agent started to arrive. Shortly after noon, there were at least 19 officers inside the hallway outside of the classroom, McCraw said.
At 12:15 p.m., tactical officers arrived, and the suspect fired again. About six minutes later, officers began moving down the hallway toward the classroom.
At 12:50 p.m., officers entered the classroom through the door after using keys they got from the janitor, and they shot and killed Ramos, McCraw said.
Details from 911 calls inside the classroom
McCraw detailed several 911 calls that were placed from inside the classrooms, including one placed by someone from inside Room 112 at 12:03 p.m.
The call last one minute and 23 seconds. The caller whispered her location.
At 12:10 p.m., she called 911 again and told dispatch that multiple people were dead, McCraw said.
She called yet again at 12:13 p.m. and again at 12:16 p.m., informing dispatch there were 8-9 students alive.
At 12:19 p.m., another 911 call was made, this time from Room 111. But the caller hung up when another student told her to, McCraw said.
Two minutes later, at 12:21, three shots could be heard over a 911 call.
At 12:36 p.m., a student called 911 again and was told to stay on the line and be very quiet, McCraw said.
The student told 911, "He shot the door."
At 12:43, she asked 911 to "Please send the police now." She also told 911 that she could hear the police next door.
At 12:50, more shots could be heard again on the 911 call, presumably from when police entered the room, McCraw said.