The law enforcement response to the Uvalde school shooting that killed 19 children and two teachers was "an abject failure" in which a commander put the lives of officers over those of the children, Texas Department of Public Safety (DPS) Director Steven McCraw said on Tuesday.

The onsite commander made "terrible decisions" and officers at the scene lacked sufficient training, costing valuable time during which lives may have been saved, McCraw told lawmakers during a Texas Senate hearing into the May 24 mass shooting.

"There is compelling evidence that the law enforcement response to the attack at Robb Elementary was an abject failure and antithetical to everything we've learned," he added.

Many parents and relatives of the schoolchildren and staff have expressed deep anger over police actions after the gunman entered Robb Elementary School and began shooting.

One delay McCraw discussed was the search for a key to the classroom where the shooting occurred. He noted that the door was not locked and there was no evidence officers tried to see if it was secured while others searched for a key.

"There's no way ... for the subject to lock the door from the inside," he said.

Days after the shooting, the Texas DPS said as many as 19 officers waited over an hour in a hallway outside classrooms 111 and 112 before a U.S. Border Patrol-led tactical team finally made entry. McCraw reiterated that in the hearing on Tuesday.

"One hour, 14 minutes, and eight seconds, that is how long the children waited, and the teachers waited, in Room 111 to be rescued," he said.

"Three minutes after the subject entered the west building, there was a sufficient number of armed officers wearing body armor to isolate, distract and neutralize the subject. 

"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."  

The Uvalde district attorney (DA) has asked the city not to release records related to the probe into the school shooting, Mayor Don McLaughlin said in a statement. He added that to date the DA and the Department of Public Safety have not provided the city with any information on their probes.

(With input from Reuters)

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