UVALDE, Texas – Texas Gov. Greg Abbott said the gunman in a school shooting sent social media messages about his intentions half an hour before the deadly rampage.

Shortly after his revelation, former congressman Beto O’Rourke confronted Abbott about “doing nothing” about gun violence, adding a chaotic element to a Wednesday news conference addressing the attack at Robb Elementary School that left 19 children and two teachers dead Tuesday.

The shooter sent Facebook messages about 30 minutes before the rampage that he was going to shoot his grandmother, then that he had shot the woman, and finally that he was going to shoot up an elementary school, Abbott said. Facebook said the messages were  private texts.

Abbott said there was no other “meaningful forewarning of this crime,” emphasized the need for mental health services and said of the victims’ families, “what they need now more than ever is our love.”

When Abbott was about to pass the microphone to another speaker, O’Rourke, a Texas gubernatorial candidate, approached the stage with a call for action. O’Rourke was the U.S. Representative for the El Paso area when a gunman killed 23 people during a 2019 mall shooting in that city.

Before being escorted away, he said: “This is on you until you choose to do something different. This will continue to happen. Somebody needs to stand up for the children of this state or they will continue to be killed just like they were killed in Uvalde yesterday.”

The massacre took place in one fourth-grade classroom and was the state’s deadliest school shooting in modern history and the nation’s third mass shooting within weeks.

Authorities identified the gunman as Salvador Ramos, 18, but revealed no motive. State Sen. Roland Gutierrez, who was briefed by state police, said the gunman “suggested the kids should watch out” and that he had bought two assault weapons after turning 18.

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Horror, death in one classroom

The killer entered the classroom, locked the door and started shooting, said Lt. Christopher Olivarez of the Texas Department of Public Safety told CNN. Officers arriving on the scene began breaking windows around the school trying to evacuate children and teachers. Olivarez said a tactical team forced its way into the classroom and faced gunfire but was “able to shoot and kill that suspect.’’

Texas mourns another mass shooting

In the last five years, Texas has been the scene of mass shootings that killed more than 85 people. Worshippers during a Sunday sermon, shoppers at a Walmart, students on a high school campus and drivers on a highway have been the targets. The state’s conservative, Republican-controlled government is unlikely to restrict gun access despite the carnage. Last year, gun laws were actually loosened after a gunman at a Walmart in El Paso killed 23 people in a racist 2019 attack that targeted Hispanics.

“I can’t wrap my head around it,” said Democratic state Sen. Roland Gutierrez,  whose district includes Uvalde. “It’s disturbing to me as a policymaker that we have been able to do little other than create greater access to these militarized weapons to just about anyone who would want them.”

Contributing: Megan Menchaca, Austin American-Statesman; N’dea Yancey-Bragg, Trevor Hughes, Chris Kenning, USA TODAY; The Associated Press