Updated

School administrators "did not adequately prepare" for a potential shooter at Robb Elementary School in Uvalde, Texas, according to a report released by the Texas House of Representatives Investigative Committee on the Robb Elementary School shooting.

In the 77-page report released on Sunday, investigators said school administrators adopted a "regrettable culture of noncompliance" with safety and security measures leading up to the shooting on May 24 at Robb Elementary School which left 19 children and two adults dead. This noncompliance "turned out to be fatal," the report said.

They also "tacitly condoned" unsafe practices by knowingly violating or allowing others to violate rules that required doors to be closed and locked.

The report stated: "The west door to the west building was supposed to be continuously locked. When the attacker approached on May 24, 2022, it was unlocked, and he was able to enter the building there."

Uvalde Memorial

The Robb Elementary School sign is seen covered in flowers and gifts on June 17, 2022 in Uvalde, Texas, the location of a May mass shooting that killed 19 students and two teachers. (Photo by Brandon Bell/Getty Images)

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"While the school had adopted security policies to lock exterior doors and internal classroom doors, there was a regrettable culture of noncompliance by school personnel who frequently propped doors open and deliberately circumvented locks," the report stated. "At a minimum, school administrators and school district police tacitly condoned this behavior as they were aware of these unsafe practices and did not treat them as serious infractions requiring immediate correction."

The school encouraged teachers and staff to leave doors unlocked or propped open to better assist teachers who forgot their keys, the report found. 

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"In fact, the school actually suggested circumventing the locks as a solution for the convenience of substitute teachers and others who lacked their own keys," it said. 

A photo combination of a Robb Elementary School sign and the west entrance door of the school. The sign is covered in flowers and gifts on June 17, 2022 in Uvalde, Texas, the location of a May mass shooting that killed 19 students and two teachers.

A photo combination of a Robb Elementary School sign and the west entrance door of the school. The sign is covered in flowers and gifts on June 17, 2022 in Uvalde, Texas, the location of a May mass shooting that killed 19 students and two teachers. (Photo by Brandon Bell/Getty Images)

The report also revealed "multiple systemic failures," including not adequately preparing for the risk of a potential shooter.

"With hindsight, we can say that Robb Elementary did not adequately prepare for the risk of an armed intruder on campus. The school’s five-foot tall exterior fence was inadequate to meaningfully impede an intruder," the report stated.

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In addition to scrutinizing the school, the report was critical of the 376 law enforcement officers who were amassed at the school at the time of the shooting. The law enforcement officers, including nearly 150 U.S. Border Patrol agents and 91 state police officials, waited outside the school for over an hour as the gunman continued to shoot and kill students and teachers inside.

Uvalde Robb Elementary police response

Law enforcement, and other first responders, gather outside Robb Elementary School following a shooting on Tuesday, May 24, 2022, in Uvalde, Texas. (AP/Dario Lopez-Mills)

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The scathing report comes as a devastated Uvalde community continues to search for answers on how the shooting took place. 

Fox News' Adam Sabes contributed to this report.