Law enforcement officials in Uvalde, Texas are facing increased scrutiny over their response to a shooting that left 19 children and two faculty members dead as questions continue to rise regarding how quickly police responded to the crime and neutralized the suspect.

Police say they first received a call of "a crashed vehicle and an individual armed with a rifle making his way into the school" at 11:30 a.m after 18-year-old Salvador Ramos crashed the truck he had taken from his grandmother’s house after shooting her in the face.

Authorities say they received a 911 call from Ramos's grandmother but an exact time has not been provided.

"He walks around. He sees two witnesses at a funeral home across the street. He fires toward them. He continues walking towards the school. He climbs a fence. Now he’s in the parking lot shooting at the school multiple times," Regional Director for DPS South Texas Victor Escalon said Thursday.

Ten minutes later, at 11:40 a.m., police say Ramos was inside Robb Elementary School after gaining access through an unlocked door without encountering any resistance. Authorities at first said that an armed officer was present at the school and injured after being shot by Ramos but later confirmed that was not the case.

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Vigil for victims of mass shooting

A vigil in the center of Uvalde, Texas honoring the 19 students and 2 teachers shot in the deadly mass shooting. (Fox News Digital)

"He walks, and I’m going to approximate 20 or 30 feet, he makes a right and walks into the hallway, he makes a right, makes another 20 feet, turns left into a schoolroom, into a classroom that has doors open in the middle," Escalon explained.

Three minutes later, Robb Elementary announced it was entering a lockdown "due to gunshots in the area" and said that students and staff were "safe in the building."

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At 11:44 a.m., fourteen minutes after the 911 call warning of an armed man walking toward the school, Uvalde police arrive and come under fire from Ramos after attempting to make entry.

"They hear gunfire. They take rounds. They move back, get cover," Escalon said. "And during that time, they approach where the suspect is at."

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Department of Public Safety Lt. Chris Olivarez told CNN that Ramos then made his way to a fourth-grade classroom and "barricaded himself by locking the door and just started shooting children and teachers that were inside that classroom."

Uvalde, Texas memorial

Stephanie and Michael Chavez of San Antonio pay their respects at a makeshift memorial outside Robb Elementary School, the site of a mass shooting, in Uvalde, Texas, U.S., May 25, 2022. REUTERS/Nuri Vallbona (REUTERS/Nuri Vallbona)

At 11:54 a.m., family members of the students gathered outside recorded videos showing them begging officers along the perimeter of the school to stop the shooting.

Children could be seen running out of the school at 12 p.m. as Escalon says police were taking fire, assembling "specialty equipment", evacuating students, and "developing a team to make entry to stop him."

At 12:17 p.m., Robb Elementary School posted on social media that an active shooter was on campus.

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"There is an active shooter at Robb Elementary," the school said. "Law enforcement is on site. Your cooperation is needed at this time by not visiting the campus. As soon as more information is gathered it will be shared. The rest of the district is under a Secure Status. "

At 12:23 p.m., the Uvalde Police Department posted on Facebook telling parents to pick up their children at a location five minutes from the school and that the scene was still "active."

It was initially believed that Border patrol and tactical teams arrived on the scene at 12:45 p.m. and quickly entered the room Ramos was in and shot him sometime before 1:06 p.m. 

However, it was revealed on Friday that the Border Patrol team arrived much earlier than previously thought and was on the scene between 12 and 12:15 p.m. Additionally, local police did not allow the tactical team to enter the classroom right away and instead waited roughly 40 minutes before entering.

What happened in those 90 minutes between when the first 911 call was placed and when Ramos was killed has fueled mounting public anger and scrutiny over law enforcement’s response to Tuesday’s rampage.

On Thursday, authorities largely ignored questions about why officers had not been able to stop the shooter sooner, with Escalon telling reporters he had "taken all those questions into consideration" and would offer updates later.

"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 unfolded. "We didn’t see that."

Ken Trump, president of the consulting firm National School Safety and Security Services, said the length of the timeline raised questions.

Law enforcement on scene at Robb Elementary School in Uvalde, Texas

Law enforcement work the scene after a mass shooting at Robb Elementary School in Uvalde, Texas, on Tuesday, May 25. (Jordan Vonderhaar/Getty Images)

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

On Friday, Texas Department of Public Safety Director Steven McCraw said that officers waited to enter the classroom because the commanding officer believed they were dealing with a barricaded suspect situation rather than an active shooter situation where children inside the classroom were at risk.

"He was convinced at the time that there was no more threat to the children and that the subject was barricaded and that they had time to organize" to get into the classroom, McCraw said.

Throughout the attack, teachers and children repeatedly called 911 asking for help, including a girl who pleaded: "Please send the police now," McCraw said.

Questions have mounted over the amount of time it took officers to enter the school to confront the gunman.

"Of course it was not the right decision. It was the wrong decision," McCraw said about the decision to wait to enter the classroom.

The Associated Press contributed to this report