The Justice Department said Sunday it will review the law enforcement response to the shooting in Uvalde, Texas, that left 19 students and two teachers dead.

The review comes amid mounting pressure and questions about the shifting and at times contradictory information about what happened in the shooting last Tuesday at Robb Elementary School and how police responded.

Justice Department spokesman Anthony Coley said the review would be conducted in a fair, impartial and independent manner and that the findings would be made public.

The review is being conducted at the request of Uvalde’s mayor, officials said.

In a statement, Coley said the goal of the review is “to provide an independent account of law enforcement actions and response that day, and to identify lessons learned and best practices to help first responders prepare for and respond to active shooter events.”

Handling the review is the department’s Office of Community Policing Services.

Such a review is somewhat rare and most after-action reports that come after a mass shooting are generally compiled by local law enforcement agencies or outside groups.

Authorities revealed on Friday that students and teachers repeatedly begged 911 operators for help even as a police commander told more than a dozen officers to wait in a school hallway. Officials said the commander believed that the suspect was barricaded inside an adjoining classroom and that there was no longer an active attack.

The revelation caused more grief and raised new questions about whether more lives were lost because officers did not act faster to stop the gunman, who was ultimately killed by Border Patrol tactical officers.

Biden has not spoken publicly about the police response to the shooting.

(AP)