The Uvalde, Texas, school district announced on Friday that it had suspended its entire police force after the Robb Elementary School mass shooting left 19 children and two teachers dead.
“Recent developments have uncovered additional concerns with department operations,” Uvalde Consolidated Independent School District said in a statement.
Lt Miguel Hernandez and Ken Mueller have also been placed on administrative leave “as a result of these recent developments”. Mr Mueller has chosen to retire, the district said.
The district said it has requested the Texas Department of Public Safety to provide troopers for campus and extra-curricular activities.
“We are confident that staff and student safety will not be compromised during this transition,” the district said.
The school district's decision was first reported by ABC News.
Brett Cross, whose daughter Uziyah Garcia was killed in the shooting, was part of a group of parents and families who spent weeks protesting outside the school district building to demand accountability for the poor police response.
“We did it!” Mr Cross tweeted after the district's announcement.
Uvalde pupils returned to classrooms at other schools within and around the city, while others left the district entirely. Those who began the term at Uvalde Elementary passed through a 2.4-metre-tall fence surrounding the campus.
The school district has faced blistering criticism for months over the police department's failure to intervene during the May 24 massacre.
A report issued by the Texas state legislature concluded that officers who responded to the emergency had a “lackadaisical approach” to the “chaotic” scene.
Police officer filmed sanitising hands during Uvalde school shooting
Uvalde police officials waited for more than an hour before confronting the shooter, Salvador Ramos, who was holed up in a classroom.
A report found that a police officer could have shot Ramos before he entered the school but hesitated while awaiting permission from a supervisor.
On Thursday, the school district announced it had fired a newly hired school district officer after a CNN report found that she was under investigation for her actions during the mass shooting.
Watch: Uvalde survivor testifies before US Congress
Young Uvalde survivor shares what happened during the attack
