According to a New York Times analysis of the investigation into last month’s shooting at a Uvalde, Texas elementary school, police delayed confronting the gunman for more than an hour. The Times reported Thursday that documents show police waited for protective equipment as they delayed entering the campus, even as they became aware that some victims needed medical treatment.

“More than a dozen of the 33 children and three teachers originally in the two classrooms remained alive during the 1 hour and 17 minutes from the time the shooting began inside the classrooms to when four officers made entry, law enforcement investigators have concluded,” the Times wrote in its analysis. “By that time, 60 officers had assembled on scene.”

The Times cited documents and video that appeared to indicate Pete Arredondo, the Uvalde school district police chief who has received the brunt of criticism regarding the police response to the shooting, was agonizing over the length of time it was taking to secure the equipment. The documents include transcripts of officer body cam footage.

“People are going to ask why we’re taking so long,” a man who investigators believe to be Chief Arredondo could be heard saying. “We’re trying to preserve the rest of the life.”

The Times analysis came the same day Arredondo gave his first extensive comments since the immediate aftermath of the shooting. In an interview with the Texas Tribune, Arredondo said he did not consider himself the person in charge and assumed someone else had taken control of the law enforcement response.

Arredondo also said he intentionally left behind both his police and campus radios before entering the school. Poor radio communications is among the concerns raised about how police handled the shooting response.

“Not a single responding officer ever hesitated, even for a moment, to put themselves at risk to save the children,” the Tribune quoted Arredondo as saying. “Our objective was to save as many lives as we could, and the extraction of the students from the classrooms by all that were involved saved over 500 of our Uvalde students and teachers before we gained access to the shooter and eliminated the threat.”

The Associated Press contributed to this report.