Authorities stated on Thursday that the gunman who killed 19 children and two teachers walked the grounds of the Texas elementary school without being confronted and entered the building through an unlocked entrance, providing another new account of the events leading up to the atrocity.

Police stated that Salvador Ramos, 18, was locked inside a classroom at Robb Elementary School for an hour before a tactical squad broke into the room and fatally shot him. Outside, parents pleaded with authorities to storm the premises.

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As a security measure, the Uvalde school system maintains a locked classroom door policy. The updated information from officials contrasted some earlier assertions and sparked new concerns about the timeline of events, the speed with which law enforcement responded, and the school’s safety safeguards.

Ramos crashed his pickup truck outside the school on Tuesday at 11:28 am (1628 GMT), fired six bullets at two spectators across the street, and then walked into the school at 11:40 am (1640 GMT), according to Victor Escalon, a representative for the Texas Department of Public Safety.

Two responding cops entered the school four minutes later, according to Escalon, but took cover as Ramos fired multiple bullets at them. He holed himself in a fourth-grade classroom and shot his victims, predominantly 9- and 10-year-olds, in the bloodiest school massacre in the United States in over a decade.

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When asked if officers should have entered sooner, Escalon responded, “That’s a tough question,” adding that officials would provide more information as the investigation progressed. After the initial exchange of gunfire, he recounted a chaotic situation in which officers called for backup and evacuated kids and personnel.

The more comprehensive testimony came hours after video emerged of distraught parents outside the school during the attack, pleading with authorities to storm the building, with some fathers being detained.

Parents can be seen smashing through yellow police tape and yelling at authorities to enter the facility in one video shared on Facebook by a man named Angel Ledezma.

“It’s already been an hour, and they still can’t get all the kids out,” stated Ledezma in the video. He did not react promptly to a request for comment.

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Another YouTube video shows authorities restraining at least one adult. One female voice can be heard saying, “Why let the children die? There’s shooting in there. “

“We got guys going in to get kids,” one officer tells the crowd. “They’re working.”

Escalon told reporters that there was no armed police officer stationed at the school. The gunman opened fire more than 25 times at the start of the incident, according to Escalon.

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The shooting, the latest in a series of mass shootings in recent years, has sparked a national discussion about the country’s gun restrictions. Despite Republican opposition, President Joe Biden and his Democratic colleagues have vowed to press for tougher limitations.

Escalon stated that investigators are still working to uncover a motive. Ramos, a high school dropout, had no criminal record and no mental disease background. Governor Greg Abbott claimed on Wednesday that Ramos had texted someone minutes before that he was planning to “shoot up an elementary school.”

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Ramos began his spree at home, shooting his grandma in the face before fleeing in a pickup truck. His grandma, who is in serious condition at the hospital, dialled 911.

A fourth-grader in the classroom told a CBS affiliate in San Antonio that the gunman started firing before entering, then crouched down and stated, “It’s time to die.”

The child, who was not identified by the station, said he hid under a table until police entered the classroom, sparking an exchange of gunshots.

At least 17 people, including children, were also injured.

Victims’ families used social media to express their grief at the loss of children who never returned home from school.

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“We told her we loved her and would pick her up after school,” Kimberly Mata-Rubio said on Facebook in memory of her fourth-grade honour student, Alexandria Aniyah Rubio. “We had no idea this was goodbye.”

According to US Census data, Uvalde has approximately 16,000 residents, nearly 80 percent of whom are Hispanic or Latino. Many people in the close-knit neighbourhood knew some of the victims or their families.