(UVALDE, Texas) -- A small town in rural Texas is reeling after a gunman opened fire at an elementary school on Tuesday, killing 19 children.
Two teachers were also among those killed at Robb Elementary School in Uvalde, according to authorities.
Prior to opening fire at the school, the suspect also allegedly shot his grandmother, officials said.
The alleged gunman -- identified by authorities as 18-year-old Salvador Ramos, a student at Uvalde High School -- is dead.
Here's how the news is developing. All times Eastern:
May 28, 1:14 pm
Texas active shooter training instructs 'move in, confront attacker,' manual shows
The Uvalde Consolidated Independent School District in Texas hosted active shooter training for its six-member police force two months prior to the massacre at Robb Elementary, based on the "Active Shooter Response for School-Based Law Enforcement" course from the Texas Commission on Law Enforcement, which explicitly states: "First responders to the active shooter scene will usually be required to place themselves in harm's way and display uncommon acts of courage to save the innocent."
The course manual also includes this sobering instruction: "A first responder unwilling to place the lives of the innocent above their own safety should consider another career field."
The training makes clear the "first priority is to move in and confront the attacker."
It is "safer" and "preferable" to have a team of at least four officers move on a subject but, since "time is the number one enemy during active shooter response," even a single officer is expected to act, according to the training document.
In Uvalde, 19 officers entered the school but remained in the hallway, Texas Department of Public Safety Director Steven McCraw said at a press conference Friday.
Only when an attacker is isolated and "can do no more harm to students, staff, or visitors" is the officer not obligated to enter the room, which is what McCraw said the incident commander, Uvalde ISD Chief Pete Arredondo, believed.
"It was the wrong decision," McCraw said.
-ABC News' Mike Levine and Aaron Katersky
May 27, 5:23 pm
Texas governor: 'I was misled' on police response to shooting
Texas Gov. Greg Abbott said he was "misled" about the response to the Uvalde school shooting.
"I am livid about what happened," Abbott said during a press briefing Friday, hours after the Texas Department of Public Safety detailed missteps that led to a 35-minute wait to breach the classroom where the shooter was.
"As everybody has learned, the information that I was given turned out, in part, to be inaccurate, and I'm absolutely livid about that," Abbott said Friday. "There are people who deserve answers the most, and those are the families whose lives have been destroyed. They need answers that are accurate, and it is inexcusable that they may suffer from any inaccurate information whatsoever."
The governor said there will be investigations into the release of information on the shooting and the strategy employed in the response.
On Wednesday, Abbott said an officer had confronted the shooter at the entrance to the school building, which was not the case.
"But the reality is, as horrible as what happened, it could have been worse," he also said at the time. "The reason it was not worse, is because law enforcement officials did what they do."
May 27, 4:37 pm
Texas official says gunman had 1,657 rounds of ammunition
The gunman had purchased a total of 1,657 rounds of ammunition, 315 of which were inside the school, Steven McCraw, director of Texas Department of Public Safety, said Friday.
McCraw said 142 of those rounds were spent cartridges and 173 were live rounds.
Officials found 922 rounds outside of the school, but on school property. Of those rounds, 22 were spent cartridges and 900 were live rounds. Another 422 live rounds were found at the crash site, McCraw said.
The suspect had a total of 60 30-round magazines, 58 of which were at the school. He had fired nearly 200 rounds, most of them inside the school, said McCraw.
May 27, 3:42 pm
5 of 17 injured in shooting remain hospitalized
Five of the 17 people injured in the elementary school shooting remain in the hospital on Friday, according to officials.
Two children and one adult are being treated at University Hospital in San Antonio, two of whom are in serious condition, and two adults are at Brooke Army Medical Center, both in fair condition.
A 10-year-old girl was discharged from University Health in San Antonio.
Eight children and three adults were treated and discharged from Udalve Medical Center earlier this week.
-ABC News' Jennifer Watts
May 27, 3:13 pm
Texas DPS conducting review of law enforcement actions during shooting
As part of its ongoing investigation into Tuesday's shooting, the Texas Department of Public Safety is conducting a review of law enforcement actions.
This comes after the visibly shaken Steven McCraw, the director of the Texas Department of Public Safety, revealed a cascading series of police failures before and during one of the deadliest school shootings in the nation’s history.
The incident commander, the chief of Uvalde ISD Police, wrongly believed the incident had transitioned from an active shooter situation to a barricaded subject situation, where the suspect had stopped firing and barricaded himself in a classroom, no longer posing a threat to children, McCraw said.
“He thought there was time,” McCraw said.
McCraw said there may have been a belief by the incident commander that no one was alive anymore inside the classrooms. But, he detailed multiple 911 calls made from inside the classrooms, on which callers explicitly said several children were alive and trapped inside with the shooter. Callers at several points asked for police to be sent in.
-ABC News' Aaron Katersky
May 27, 1:53 pm
Several 911 calls were made from inside classroom as police waited outside
Those inside a classroom with the shooter made several calls to 911, but the tactical unit that arrived at 12:15 p.m. waited 35 minutes before breaching the classroom, Steven McCraw, director of Texas Department of Public Safety, said at a press conference Friday.
A 911 call was made at 12:03 p.m. from room 112 and lasted 23 seconds. McCraw did not identify the caller.
She called back at 12:10 p.m. and advised that there were multiple dead in the classroom, McCraw said.
The person then called again at 12:13 p.m. and again at 12:16 p.m., when she said there were eight to nine students who were still alive, McCraw said.
A call was made by someone else from room 111 at 12:19 p.m., the caller hung up when another student told her to hang up, McCraw said.
At 12:21 p.m., three shots were heard over a 911 call. At 12:36 p.m., another 911 call was made by the initial caller and it lasted for 21 seconds. The student caller was told to stay on the line and be very quiet. She told 911 that the gunman shot the door, McCraw said.
At approximately 12:43 p.m. and 12:47 p.m., she asked 911 to please send the police now, McCraw said.
The caller said she could hear police next door at 12:46 p.m. At 12:50 p.m., the Border Patrol tactical unit finally breached the door and shot the suspect.
May 27, 1:18 pm
Suspect reportedly involved in online chats about guns, school shootings in recent weeks
Authorities shed more light on some of the suspect's digital footprint in the weeks and months before Tuesday's mass shooting.
In September 2021, suspected gunman Salvador Ramos asked his sister to buy him a gun and she "flatly refused," Steven McCraw, director of the Texas Department of Public Safety, told reporters during a briefing Friday. He did not note where this exchange took place.
On Feb. 28, in an Instagram group chat with four people, they discussed "Ramos being a school shooter," McCraw said.
The next day, on March 1, in an Instagram chat with four people, Ramos discussed buying a gun, according to McCraw.
Two days later, on March 3, in another four-person chat, someone said, "Word on the street is you are buying a gun," according to McCraw. Ramos reportedly replied, "Just bought something."
On March 14, Ramos posted on Instagram, "Ten more days," according to McCraw. Someone replied, "Are you going to shoot up a school or something?" to which Ramos replied, "No. Stop asking dumb questions. You'll see," according to McCraw.
Investigators are also looking into people the suspect may have communicated with in video game chat rooms who "may have known something," McCraw said.
May 27, 12:36 pm
Officers did not breach classroom for 35 minutes while shooter was inside
Steven McCraw, director of Texas Department of Public Safety, admitted it was the "wrong decision" for officers not to go into the classroom where the suspect was for 35 minutes. Children were inside the classroom with him, making 911 calls, McCraw said in a press conference Friday.
The incident commander believed he was dealing with was a barricaded subject inside the school and the children were not at risk, he said.
A tactical team from CBP was on scene at 12:15 p.m., but did not breach the classroom until 12:50 p.m.
“Of course it wasn’t the right decision,” McCraw said. “It was the wrong decision.”
May 27, 11:23 am
US Marshals say they never arrested or handcuffed anyone outside school
The U.S. Marshals said they never placed anyone in handcuffs, but they say they “maintained order and peace in the midst of the grief-stricken community that was gathering around the school," in a statement posted on Twitter.
U.S. Marshals arrived on scene from Del Rio, Texas, at 12:10 p.m., and the first deputy U.S. Marshal went into the school to assist BORTAC, the elite tactical CBP team that ultimately shot the alleged shooter, the statement said.
They came from 70 miles away and got the first call around 11:30 a.m., according to the statement.
“These Deputy US Marshals also rendered emergency trauma first aid for multiple victims,” the statement said.
"Additional Deputy U.S. Marshals were asked to expand and secure the official law enforcement perimeter around the school,” the statement said. “Our hearts are heavy with sorrow and sadness at this horrific crime. We send our condolences to all the victims and families affected by this tragedy."
Angeli Rose Gomez, a mother waiting outside for her children, told the Wall Street Journal she was one of numerous parents urging police and law enforcement officers to go into the school sooner, first politely and then more urgently. She said U.S. Marshals put her in handcuffs, and told her she was being arrested for intervening in an active investigation.
Angel Garza, the stepfather of one of the children killed in the shooting, ran to try to reach and help his child, and was restrained and handcuffed by a local police officer, Desirae Garza, the girl's aunt, recounted to the New York Times.
May 27, 6:30 am
10-year-old survivor recalls gunman saying: 'You're all gonna die'
There was blood in the hallway and children were covered in it, one of the students who survived the mass shooting at Robb Elementary School in Uvalde, Texas, told ABC News.
Salinas was a student in Irma Garcia's fourth-grade class. They were scheduled to graduate Thursday, but the ceremony was canceled because Garcia, another teacher and 19 third- and fourth-grade students were killed in Tuesday's massacre.
Salinas said his aunt dropped him off for school on Tuesday morning.
"It was a normal day until my teacher said we're on severe lockdown," he told ABC News, "and then there was shooting in the windows."
Salinas said the gunman came into his classroom, closed the door and told them, "You're all going to die," before opening fire.
"He shot the teacher and then he shot the kids," Salinas said, recalling the cries and yells of students around him.
-ABC News' Samira Said
May 26, 9:57 pm
Accused shooter's mother at one point worked at same establishment of gun purchase: Sources
Sources told ABC News the accused school shooter’s mother, Adriana Reyes, at one point worked at Oasis Outback, the same store where the gunman purchased two weapons just after his 18th birthday earlier this month.
The establishment is half gun retailer, half restaurant; Reyes’ employment was with the restaurant portion, sources say.
It is unclear if she had any role in her son’s purchase of the firearms. The owner of Oasis declined to comment to ABC News and added he would only speak with law enforcement at this time. Reyes has not responded to ABC News’ request for comment.
-ABC News' Matt Gutman, Laura Romero and Victor Ordonez
May 26, 6:49 pm
Law enforcement examining if lockdown was audible to students, staff: Sources
The response by school officials and law enforcement is becoming a key focus in the ongoing investigation into the Uvalde school shooting, law enforcement sources told ABC News Thursday.
It is unclear whether any students and teachers heard an official call for a lockdown once the gunman entered the building, the sources said.
Additionally, investigators are looking into whether officers on site could have made other attempts to enter the school to end the gunman’s rampage faster, the sources said. Responding police were met with gunfire and called for tactical teams with proper equipment to enter the classroom and neutralize the gunman, according to the sources.
-ABC News' Matt Gutman, Josh Margolin, Aaron Katersky and Luke Barr
May 26, 5:19 pm
10-year-old survivor recalls moments after hearing shots fired
A student who was in the classroom next door to the one the gunman entered recounted to ABC News what she did next.
Gemma Lopez, 10, said she heard five to six gunshots and commotion outside her classroom at Robb Elementary School before a bullet whizzed by her arm and into the wall. She recalled seeing a puff of smoke, which is when she knew they were all in danger.
She said she turned off the lights and then ducked under the tables -- what she learned to do in the active shooter training she has undergone since kindergarten. There were no locks inside and they did not have a key in the classroom to lock the door from the inside, she said.
Authorities yelled at the gunman to put down his weapon, to which he reportedly shouted in response, "Leave me alone please," in Spanish, Gemma recalled.
Gemma said her best friend, Amerie Jo Garza, was one of the 19 children killed in the massacre.
-ABC News' Matt Gutman and Olivia Osteen
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