Uvalde’s pain is only getting worse after a week.

The initial details of the evil unleashed on defenseless schoolchildren by an 18-year-old armed with a legally purchased semi-automatic rifle were incomprehensible. Everything that has happened since has only added to the horror. And, while the Robb Elementary School tragedy is primarily a personal one for families dealing with the unbearable loss of children at the start of their lives, it is also a national trauma that has heightened in the last seven days as every parent, and many children, face fears about whether their towns will be next.

Over the holiday weekend, new developments in the aftermath of the mass killing of 19 elementary school students and two teachers raised new concerns about the law enforcement response as a massacre unfolded inside the school.

Despite years of experience to the contrary, President Joe Biden, after visiting Texas to console the bereaved, expressed hope that “rational” Republicans would join an effort to pass new firearm laws to prevent another community from being subjected to the same terror.

Disturbing new evidence emerged of a child calling 911 for assistance from a “room full of victims” as police delayed storming the school in an apparent and potentially fatal deviation from active-shooter protocols in place for years. The apparent dispatch audio alerts officers on the scene to what is going on inside the school, raising concerns about the delay in engaging the shooter. CNN has not been able to independently confirm the audio’s source. It does, however, provide a heartbreaking glimpse into the horrific moments children endured inside the classroom, dialing emergency services multiple times and pleading for help.

The audio adds to the haunting possibility that a quicker police response could have saved young lives, and it will be central to a web of official investigations. CNN previously reported that up to 19 officers were inside the school more than 45 minutes before the suspect was killed, and that the school district police chief decided not to order a classroom breach. On CNN’s “State of the Union” on Sunday, Texas state Sen. Roland Gutierrez told Dana Bash that “so many things went wrong here” and that mistakes may have cost lives. He also revealed that when Customs and Border Protection officers arrived at the school, they were frustrated by the failure to confront the shooter and eventually went inside.

These new lines of inquiry will be included in a US Department of Justice investigation announced on Sunday in response to a request from Uvalde Mayor Don McLaughlin. The investigation will almost certainly look into why commonly taught active-shooter protocols established after the Columbine school massacre in 1999, which require assailants to be stopped as soon as possible, were apparently not followed. Other questions surround the training of school district police officers, the quality of their leadership, whether the necessary equipment was on hand at the scene, and whether rivalries or disconnects between law enforcement agencies hampered the response. First-person accounts of what happened at chaotic disaster scenes frequently change as a more complete picture of events emerges.

However, it appears that something went horribly wrong from the start of the investigation. Former Secret Service special agent and CNN Law Enforcement Analyst Jonathan Wackrow called the response “one of the worst police failures in modern US history.”

On Monday, the first services for the 19 children whose lives were brutally ended in their classroom after less than a decade on Earth were held. The testimony of those left behind encapsulated the broken promise of lives cut short, as well as the bravery of parents facing the unthinkable.

“It brings me joy to know that I had the opportunity to have such a wonderful daughter, and I tried to be the best father that I could be,” Alfred Garza, Amerie Jo Garza’s father, said on Friday. On Monday, a rosary and visitation were planned for Amerie. Services were also planned for another 10-year-old, Maite Rodriguez, who aspired to be a marine biologist when she grew up.