Nearly 20 officers stood for about 45 minutes in the hallway outside the classrooms of a Texas school where a gunman killed 19 children and two teachers this week before Border Patrol agents opened the door to confront and kill him. The authorities recognized today, who also accepted that it was a wrong decision.

Steven McCraw, the head of the Texas Department of Public Safety, acknowledged during a controversial press conference that the actions of the agents were not as expected.

The commander at the scene believed the shooter, identified as 18-year-old Salvador Ramos, was barricaded inside the classroom and the children were not in danger, McCraw said.

“It was the wrong decision. Point,” the official acknowledged.

“The doctrine requires, no matter what agency you belong to, you don’t have to have a leader on the scene, every officer has to line up, look for where the shots are coming from, and keep firing until the shooter is killed. Period,” McCraw said, visibly upset.

As he explained, the leader of the 19 agents believed that he was facing a situation of an individual at a barricade and not an active shooter.

A barricade is defined as a subject confined within a location/position – with or without hostages – possibly armed and believed to have committed a crime or to be a danger to self or others.

Instead, an active shooter is a subject who engages in a random or systematic act of violence that demonstrates intent to continually inflict death or serious bodily injury on others.

“Now I know he was an active shooter,” McCraw said, recalling several times that he was not at school when the events occurred. “But if the shooting continues and there are individuals alive, you have an obligation to go back into an active shooter stance and that means all (officers) have to move” toward the shooter.

McCraw made the remarks as he released new details about the attack in which Ramos killed 19 children and two teachers, though his motive remains unclear.

There was a round of shots shortly after Ramos entered the room where officers ended up killing him, but those shots were “sporadic” for much of the 48 minutes officers waited in the hallway, McCraw said.

Throughout the attack, teachers and children repeatedly called 911 for help, including one girl who pleaded, “Please send the police in now,” McCraw said.

After the statements of the last few days, questions have increased about the time it took for the agents to enter the school to confront the gunman.

It was 11:28 a.m. Tuesday when Ramos’ Ford truck crashed into a ditch behind the low-rise Texas school and he jumped out carrying an AR-15-style rifle.

But it wasn’t until 12:58 p.m. that the radio conversations of the security forces said that Ramos had been killed and that the siege had ended.

What happened in those 90 minutes, in a working-class neighborhood near the outskirts of the city of Uvalde, has fueled growing public anger and scrutiny over law enforcement’s response to Tuesday’s massacre.

“They say they rushed it,” said Javier Cazares, whose fourth-grade daughter, Jacklyn Cazares, was killed in the attack, and who ran to the school as the massacre unfolded. “We didn’t see that.”

Friday’s briefing came after authorities spent three days providing often conflicting and incomplete information.

According to the new timeline provided by McCraw, after crashing his truck, Ramos shot two people who were leaving a nearby funeral home.

At 11:33 p.m., Ramos entered the school through a back door that had been opened by a teacher who came out to watch the truck crash and fired more than 100 bullets into a couple of classrooms, McCraw said.

Two minutes later, three local police officers arrived and entered the building through the same door, followed shortly by four others, McCraw said.

Within 15 minutes, up to 19 agents from different agencies had gathered in the corridor, receiving sporadic shots from Ramos, who was taking refuge in a room.

Ramos was still inside the school at 12:10 p.m. when the first agents of the United States Marshals Service arrived. They had rushed to school from nearly 70 miles (113 kilometers) away in the border city of Del Rio, the agency said in a tweet Friday.

But the police commander inside the building decided the group should wait to confront the gunman, believing the scene was no longer an active attack, McCraw said.

The crisis came to an end after a group of Border Patrol tactical agents entered the school, unlocked the classroom door with a skeleton key, and attacked Ramos. Just before 1 p.m., he was dead.

Ken Trump, president of the consultancy National School Safety and Security Services, said the length of the deadlines raised questions.

“Based on best practices, it’s very hard to understand why there was any kind of delay, especially when it’s reported that it took 40 minutes or more to neutralize the shooter,” he said.

The motive for the massacre — the nation’s deadliest school shooting since Sandy Hook nearly a decade ago — remained under investigation, and authorities said Ramos had no known criminal or mental health history.