UVALDE, Texas (AP) — The state agency investigating the mass shooting at an elementary school in Uvalde has determined that the commander facing criticism for the slow police response was not carrying a radio as the massacre unfolded, a Texas state senator said Friday.

Sen. Roland Gutierrez told The Associated Press in a brief telephone interview that a Texas Department of Public Safety official told him school district police Chief Pete Arredondo was without a radio during the May 24 attack by a lone gunman at Robb Elementary School that left 19 students and two teachers dead. Seventeen more people were injured.

Authorities have not said how Arredondo was communicating with other law enforcement officials at the scene, including the more than a dozen officers who were at one point waiting outside the classroom where the gunman was holed up. Arredondo heads the district’s small department and was in charge of the multi-agency response to the shooting.

Texas state Sen. Roland Gutierrez speaks during a news conference at a town square in Uvalde, Texas, Thursday, June 2, 2022. Gutierrez said the commander at the scene of a shooting at Robb Elementary School was not informed of panicked 911 calls from inside the school building. (AP Photo/Jae C. Hong)

He has not responded to multiple interview requests from AP since the attack, including a telephone message left with district police Friday.

The apparently missing radio is the latest detail to underscore concerns about how police handled the shooting and why they didn’t confront the gunman faster, even as anguished parents outside the school urged officers to go inside. The Justice Department has said it will review the law enforcement response.

Focus has turned to the chief in recent days after Steven McCraw, the head of the Texas Department of Public Safety, said Arredondo believed the active shooting had turned into a hostage situation, and that he made the “wrong decision” to not order officers to breach the classroom more quickly to confront the gunman.

Gutierrez, who represents Uvalde, complained Thursday that Arredondo was not informed of panicked 911 calls coming from students trapped inside a classroom where the gunman had holed up. The Democrat called it a “system failure.”

Police radios are a crucial source of real-time communication during an emergency and, according to experts, often how information from 911 calls is relayed to officers on the ground. It’s unclear who at the scene was aware of the calls. Uvalde police did not respond to questions about the calls Thursday.

The news emerged amid tensions between state and local authorities over how police handled the shooting and communicated what happened to the public.

The gunman in Uvalde, 18-year-old Salvador Ramos, spent roughly 80 minutes inside the school, and more than an hour passed from when the first officers followed him into the building and when he was killed by law enforcement, according to an official timeline.

Ramos slipped through an unlocked door into adjoining fourth-grade classrooms at 11:33, authorities said. He rapidly fired off more than 100 rounds.

FILE – Investigators search for evidences outside Robb Elementary School in Uvalde, Texas, May 25, 2022, after an 18-year-old gunman killed 19 students and two teachers. Uvalde Consolidated Independent School District Police Chief Pete Arredondo, who served as on-site commander during the shooting, said that he’s talking daily with investigators, contradicting claims from state law enforcement that he has stopped cooperating. (AP Photo/Jae C. Hong, File)

Officers entered minutes later, exchanging fire with Ramos, and by 12:03 there were as many as 19 officers in the hallway outside the classroom, McCraw said. Authorities have not said where Arredondo was during this period.

Officers from other agencies urged the school police chief to let them move in because children were in danger, according to two law enforcement officials who spoke on condition of anonymity because they had not been authorized to discuss the investigation publicly.

A U.S. Border Patrol tactical team used a school employee’s key to unlock the classroom door and kill the gunman around 12:50 p.m., McCraw said.

Since the shooting, law enforcement and state officials have struggled to present an accurate timeline and details of the event and how police responded, sometimes providing conflicting information or withdrawing statements hours later. State police have said some accounts were preliminary and may change as more witnesses are interviewed.

Gutierrez said Friday that a Texas Department of Public Safety official told him that the Uvalde-area district attorney, Christina Mitchell Busbee, had directed the agency to not release more information about the shooting investigation to the senator or the public.

The Department of Public Safety on Friday referred all questions about the shooting investigation to Busbee, who has not returned telephone and text messages seeking comment.

Gutierrez said Thursday that many people should shoulder some blame in the Uvalde shooting, including the Texas governor.

“There was error at every level, including the legislative level. Greg Abbott has plenty of blame in all of this,” he said.