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 Tuesday.

The on-site 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," McCraw said.