The gunman’s final 90 minutes raise concerns about police delays.

The Ford pickup slammed into a ditch behind the low-slung Texas school at 11:28 a.m., and the driver jumped out carrying an AR-15-style rifle.

Authorities say Salvador Ramos, 18, was in the hallways of Robb Elementary School 12 minutes later. He soon found himself in a fourth-grade classroom. In an unfathomable outburst of violence, he slaughtered 19 schoolchildren and two teachers.

The siege was lifted at 12:58 p.m., according to law enforcement radio chatter.

What happened in those 90 minutes in a working-class neighborhood near the outskirts of the small town of Uvalde has fueled public outrage and scrutiny of law enforcement’s response to Tuesday’s rampage.

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

Authorities largely ignored questions about why officers were unable to stop the shooter sooner on Thursday, with Victor Escalon, regional director for the Texas Department of Public Safety, telling reporters he had “taken all those questions into consideration” and would provide updates later.

The media briefing, called by Texas officials to clarify the timeline of the attack, revealed previously unknown details. However, by the time it ended, it had added to the troubling questions surrounding the attack, such as the time it took police to arrive on the scene and confront the gunman, as well as his apparent failure to lock a school door he entered.

Investigators said after two days of providing often contradictory information that a school district police officer was not inside the school when Ramos arrived and that, contrary to previous reports, the officer had not confronted Ramos outside the building.

Instead, they drew a timeline that was notable for unexplained delays by law enforcement.

Ramos opened fire on two people coming out of a nearby funeral home after his truck crashed, according to Escalon. At around 11:40 a.m., he entered the school “unobstructed” through an apparently unlocked door.

However, the first officers arrived on the scene 12 minutes after the crash and did not enter the school to pursue the shooter until four minutes later. Ramos’ gunfire drove them back inside, where they took cover, according to Escalon.

“Based on best practices, it’s very difficult to understand why there were any types of delays, particularly when you get reports of going in to neutralize that shooter for 40 minutes and up,” he said.

Many other aspects of the case and response remained unknown. The motive for the massacre — the deadliest school shooting in the United States since Newtown, Connecticut, almost a decade ago — remained unknown, with authorities saying Ramos had no known criminal or mental health history.

According to witnesses, frustrated onlookers urged police officers to charge into the school during the siege.

“Enter there! “Go in there!” women yelled at the officers shortly after the attack began, according to Juan Carranza, 24, who was standing outside a house across the street.

Carranza believes the officers should have arrived at the school earlier: “There were more of them.” He was the sole survivor.”

Border Patrol Chief Raul Ortiz did not provide a timetable, but emphasized that the tactical officers from his agency who arrived at the school did not hesitate. He claimed they moved quickly to enter the building, forming a “stack” behind an agent holding a shield.

“What we wanted to make sure of was that those agents acted quickly and swiftly,” Ortiz told Fox News.

The crisis ended about an hour later, at 12:45 p.m., when a group of Border Patrol tactical officers entered the school, according to Texas Department of Public Safety spokesperson Travis Considine. They exchanged gunfire with the gunman, who was holed up in the fourth-grade classroom. He died shortly before 1 p.m.

During that time, the officers called for backup, negotiators, and tactical teams, while also evacuating students and teachers, according to Escalon.

The length of the timeline, according to Ken Trump, president of the consulting firm National School Safety and Security Services, raises concerns.

However, according to a law enforcement official, once inside the building, the agents had difficulty breaching the classroom door and had to rely on a staff member to open the room with a key. The official spoke on the condition of anonymity because he was not authorized to discuss the investigation publicly.

Lt. Christopher Olivarez, a spokesman for the Department of Public Safety, told CNN that investigators were attempting to determine whether the classroom was indeed locked or barricaded in some way.

When Cazares arrived, he noticed two officers outside the school and about five others escorting students out. However, he claimed that 15 or 20 minutes passed before officers with shields arrived to confront the gunman.

As more parents arrived at the school, he and others urged police to intervene, according to Cazares. He heard four gunshots before being told to return to a parking lot with the others.

“Many of us were arguing with the cops, saying, ‘You all need to go in there.'” You must all do your jobs.’ “Their response was, ‘We can’t do our jobs because you’re interfering,'” Cazares explained.

According to a law enforcement official who was not authorized to discuss the case and spoke on the condition of anonymity, the armed school officer was driving nearby but was not on campus when Ramos crashed his truck.

According to the law enforcement official, investigators concluded that the school officer was not placed between the school and Ramos, preventing him from confronting the shooter before he entered the building.

Michael Dorn, executive director of Safe Havens International, which works to make schools safer, cautioned that it can be difficult to get a clear understanding of the facts immediately following a shooting.

“The information we have a few weeks after an event is usually quite different from what we have in the first day or two.” “And even that is frequently inaccurate,” Dorn said. “You’re usually eight to twelve months out before you really have a decent picture” for catastrophic events.