UVALDE, Texas (KXAN) — As more details emerge following Tuesday’s mass shooting at Robb Elementary School in Uvalde, Texas, investigators are beginning to piece together a clearer timeline of the shooter’s actions leading up to the attack.

Salvador Ramos, an 18-year-old from Uvalde, was identified as the suspect responsible for killing at least 19 children and two adults Tuesday. Ramos was killed by responding officers.

The shooting began around 11:30 a.m. Tuesday, said Pete Arredondo, chief of police for the Uvalde Consolidated Independent School District. By 12:15 p.m., the entire school district had already gone on lockdown and Uvalde CISD posted about the active shooter situation on social media.

But prior to that, Gov. Greg Abbott and law enforcement officials said the shooter had attacked and shot his grandmother. Around 11 a.m. — approximately 30 minutes before entering the school — the shooter sent the following messages via direct messages, as clarified by a Meta spokesperson:

  • First message: “I’m going to shoot my grandmother”
  • Second message: “I shot my grandmother”
  • Third message: “I’m going to shoot an elementary school”

As of 1:30 p.m. Tuesday, Uvalde Memorial Hospital posted it was “caring for several students in the ER.” A later post just before 3 p.m. confirmed UMH had received 13 children via ambulance or buses for treatment. Two children had been transferred to San Antonio, another was pending transfer and two people who had arrived at UMH died from their injuries.

By 4 p.m. Tuesday, it had been confirmed at least 14 children and one teacher were killed during the shooting. Speaking at a press conference from Abilene, Abbott said the shooter was dead and had been killed by responding officers. Previously, the Uvalde Police Department had said the shooter was in custody.

Abbott explained during his press conference the Uvalde CISD Police Department will serve as the primary lead on the investigation but will receive investigative and patrol assistance from state resources.

During an afternoon press conference held by Uvalde CISD, Arredondo said it was believed the shooter had acted alone and there were no other suspects. He added the Texas Department of Public Safety is also involved in the investigation.

The Texas Department of Public Safety confirmed just before 7 p.m. Tuesday the death toll had risen to 18 children and two teachers. During a Uvalde CISD press conference Tuesday evening, Superintendent Dr. Hal Harrell confirmed the school year — which was set to end Thursday — was officially over.

“My heart is broken today,” he said. “We’re a small community, and we need your prayers to get us through this.”

The death toll rose to 19 children and two adults, as confirmed around 9 p.m. Tuesday.

During a press conference Wednesday afternoon, Abbott confirmed the shooter had legally purchased two AR-style rifles shortly after his 18th birthday on May 16, along with 375 rounds of ammunition. Abbott said only one rifle was used during the shooting.

Texas DPS Director Steven McCraw recounted Wednesday that Ramos drove his grandmother’s vehicle and crashed it outside the school. The shooter then exited with a backpack and rifle and went to the backdoor of the campus.

McCraw said a school district police officer approached the shooter, but no gunfire was exchanged. Ramos then entered the school and made his way into a connected two-room classroom, where the victims were killed.

A law enforcement official familiar with the investigation said the Border Patrol agents had trouble breaching the classroom door and had to get a staff member to open the room with a key. The official spoke on the condition of anonymity because he was not authorized to speak publicly about the ongoing investigation.

McCraw explained it was “within 40 minutes or so” from when Ramos opened fire on the school security officer and when the SWAT-like Border Patrol team shot him. Law enforcement officials later said it was unclear if the gunman and the security officer had fired on one another.

According to Abbott, the shooter didn’t have a known criminal or mental health history, but the investigation into his background and possible motive is ongoing.

Abbott said through conversations with law enforcement personnel, they said there’s “a problem with mental health illness in this community.”

“There is an urgent need for everybody affected to access mental health,” Abbott said.

The Associated Press contributed to this report.