The former state trooper was among the new officers hired by the district.
A police officer who was hired by the Uvalde school district despite being under investigation for her conduct during the school massacre while with the Texas Department of Public Safety has now been fired.
The school district said in a letter Thursday that Crimson Elizondo had been fired effective immediately. The decision to hire Elizondo drew outrage from parents' of victims of the May 24 school shooting that killed 21 people, including 19 elementary school students.
"We are deeply distressed by the information that was disclosed yesterday evening concerning one of our recently hired employees, Crimson Elizondo," the school district wrote in the letter. "We sincerely apologize to the victim's families and the greater Uvalde community for the pain that this revelation has caused."
Kimberly Rubio, whose daughter, Lexi, was killed at Robb Elementary, said the district was right to fire Elizondo, but said she shouldn't have been hired in the first place.
"As the school district that I send my children off to, I expect them to be vetted," Rubio told ABC News.
"I applied at Whataburger and had a more thorough interview," she added. "I don't understand why she herself would apply for this job. And I also don't understand why the school district would hire her."
ABC News confirmed Wednesday that Elizondo, a former Texas state trooper now under investigation for her conduct in responding to the Uvalde school shooting rampage, was among the new officers hired for the Uvalde school district police department -- the same force that has come under fire for the bungled response to the massacre.
The news was first reported by CNN.
Elizondo was the first member of the Texas Department of Public Safety to enter the hallway at Robb Elementary School after the shooter gained entry. The trooper did not bring her rifle or vest into the school, according to the results of an internal review by DPS that was detailed to ABC News.
As a result of potential failure to follow standard procedures, the trooper was among seven DPS personnel whose conduct is now being investigated by the agency's inspector general. The seven have been suspended, however, by Elizondo resigning from DPS to work for the Uvalde schools she is no longer subject to any internal discipline or penalties. Her conduct -- if found to be in violation of law or policy -- would be included in the final report from the DPS IG.
Texas DPS said Thursday it sent a memo to the Uvalde school district on July 28, which was transmitted on a secure law enforcement network on Aug. 1, saying that Elizondo was under investigation by the DPS inspector general.
On that day, Lt. Miguel Hernandez of the Uvalde Consolidated Independent School District Police Department confirmed in writing: "Got it, thank you so much, MRH." Hernandez took over control of the department after maligned former Police Chief Pete Arredondo was fired.
The Uvalde school district did not say when Elizondo was hired, but they said at a school board meeting on Aug. 8 that "four officers have been recommended for hire." It's unclear if Elizondo was one of them.
Neither Hernandez nor the district spokeswoman have responded to requests for comment.
About two dozen family members of victims had gathered outside the school district administration building before sunrise Thursday with signs to protest Elizondo's hiring.
Some families of the victims have joined to form a group called Lives Robbed. In a statement Wednesday, the group said: "We are disgusted and angry at Uvalde Consolidated Independent School District's (UCISD) decision to hire Officer Crimson Elizondo. Her hiring puts into question the credibility and thoroughness of UCISD's HR and vetting practices. And it confirms what we have been saying all along: UCISD has not and is not in the business of ensuring the safety of our children at school."
The statement continues: "We cannot trust the decisions that have been made in regard to the safety of our schools. Therefore, we are calling for all UCISD officers to be suspended, pending the conclusion of the investigation by JPPI Investigations LLC. The results of this investigation must be released to the families of the victims of the Robb Elementary shooting, as well as to the public. Our families have been calling for accountability, and we deserve transparency and justice at the state, local and federal levels. Our children have been taken from us. We will not stop fighting until we have answers and we ensure the safety of the children in our community is the top priority."
Kimberly Rubio told ABC News Thursday, "I think that the first step is investigating these officers. Putting them on suspension while you do so. Making sure that you're hiring the right people. Making sure your doors are locked, making sure the gates are up."
Despite Elizondo's firing, Rubio said, "I'm very frustrated. It's never-ending. We'll never move on, but we still deserve transparency -- accountability, justice. Nobody's helping us."
Questions were also raised about the district's pre-hiring vetting of Arredondo, who has been blamed for much of the bungled shooting response. He had been demoted in a previous job, and critics contend that work history was not taken into account when the district hired him to run its police force.
The practice of police officers switching jobs and jurisdictions despite concerns raised in prior posts has become a concern nationally. Some have called for the creation of national standards and databases that would enable prospective employers to learn quickly whether a cop has anything potentially disqualifying in their employment history.
ABC News' Patrick Linehan, Ishmael Estrada and Olivia Osteen contributed to this report.