The Uvalde school district’s police chief was put on leave Wednesday following allegations that he erred in his response to the mass shooting at Robb Elementary School that left 19 students and two teachers dead.

Uvalde Consolidated Independent School District Superintendent Hal Harrell said that he put schools police Chief Pete Arredondo on administrative leave because the facts of what happened remain unclear. In a statement, Harrell did not address Arredondo’s actions as on-site commander during the attack but said he didn’t know when details of federal, state and local investigations into the law enforcement response to the slayings would be revealed.

“From the beginning of this horrible event, I shared that the district would wait until the investigation was complete before making personnel decisions,” Harrell said. “Because of the lack of clarity that remains and the unknown timing of when I will receive the results of the investigations, I have made the decision to place Chief Arredondo on administrative leave effective on this date.”

A spokesperson for the Uvalde school district, Anne Marie Espinoza, declined to say whether Arredondo would continue to be paid while on leave.

Another officer will assume the embattled chief’s duties, Harrell said.

Col. Steven McCraw, director of the Texas Department of Public Safety, told a state Senate hearing on Tuesday that Arredondo made “terrible decisions” as the massacre unfolded on May 24 , and that the police response was an “abject failure.”

Three minutes after 18-year-old Salvador Ramos entered the school, sufficient armed law enforcement were on scene to stop the gunman, McCraw testified. Yet police officers armed with rifles waited in a school hallway for more than an hour while the gunman carried out the massacre. The classroom door could not be locked from the inside, but there is no indication officers tried to open the door while the gunman was inside, McCraw said.

McCraw has said parents begged police outside the school to move in and students inside the classroom repeatedly pleaded with 911 operators for help while more than a dozen officers waited in a hallway. Officers from other agencies urged Arredondo to let them move in because children were in danger.

“The only thing stopping a hallway of dedicated officers from entering Room 111 and 112 was the on-scene commander who decided to place the lives of officers before the lives of children,” McCraw said.

Uvalde Mayor Don McLaughlin pushed back on McCraw’s testimony casting blame on Arredondo, saying the Department of Public Safety has repeatedly put out false information about the shooting and glossed over the role of its own officers.

McLaughlin called Tuesday’s Senate hearing a “clown show” and said he heard nothing from McCraw about state troopers’ involvement, even though McLaughlin said their number in the school hallway at points during the slaughter surpassed that of any other law enforcement agency.

Delays in the police response as the shooting was happening has become the focus of ongoing investigations and public outcry. Law enforcement has at times offered confusing and sometimes contradictory details and timelines that have drawn anger and frustration.