UVALDE, Texas – The horrific scope of an elementary school shooting that killed 19 children and two teachers was coming into agonizing focus Thursday amid new revelations about the attack, including that the gunman barricaded himself in a fourth grade classroom where most victims died.

Some community members who had gathered outside Robb Elementary School as the drama unfolded urged police officers to charge in. Department of Public Safety Director Steve McCraw said a Border Patrol tactical team shot the gunman 40 minutes to an hour after he opened fire on a school security officer.

“The bottom line is law enforcement was there,” McCraw said. “They did engage immediately. They did contain (the gunman) in the classroom.”

Javier Cazares, whose fourth grade daughter, Jacklyn Cazares, was killed in the attack, said he arrived at the scene while police were still gathered outside the building. Upset that police were not moving in, he raised the idea of charging into the school with several other bystanders.

“Let’s just rush in because the cops aren’t doing anything like they are supposed to,” he said. “More could have been done.”

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‘Hearts are forever shattered’

As officials work to piece together what happened, grieving residents tried to comprehend the unimaginable loss and console friends and neighbors. In Uvalde, a South Texas city of 16,000 residents, nearly everyone knew a family touched by the bloodshed – either directly or indirectly. Texas Gov. Greg Abbott said 17 other people were wounded, and that the parents of each victim had been informed of their deaths. 

“To say the least, Uvalde has been shaken to its core,” said Abbott, who choked back tears in a news conference at Uvalde High School. “Families are broken apart. Hearts are forever shattered, and all Texans are grieving with the people of Uvalde.”

Beto O’Rourke challenges Gov. Abbott 

During the news conference, Abbott said the gunman sent social media messages about his intentions half an hour before the deadly rampage. Shortly after his revelation, former congressman Beto O’Rourke confronted the governor over “doing nothing” about gun violence.