Texas Department of Public Safety Director Steven McCraw told reporters Friday that law enforcement officers had made "wrong decisions" during the massacre at an elementary school earlier this week.

Police have faced angry questions over why it took more than an hour to neutralize the gunman who killed 19 children and two teachers during the attack.

'Wrong decision' in hindsight

The on-site commander had believed the gunman was barricaded in the classroom, and that the children were not at risk, McCraw said. 

The commander had instead decided to wait for a specially-trained tactical team before trying to enter the classroom at the Robb Elementary School in Uvalde. 

"From the benefit of hindsight... it was the wrong decision, period," McCraw said.

US Border Patrol agents used a master key to open the locked door, the official said. They then confronted and killed the gunman, 18-year-old Salvador Ramos, at about 12.50 p.m.

DW correspondent in Texas Stefan Simons said that McCraw's comments drew "outrage on the part of the public in Uvalde." Not only for the fatal ineptitude, but over the fact that it took days to hear from the police in the first place.

Simons said it was a "major blunder" all over again to take so long to address the police failings at the scene.

Governor Greg Abbott said he was "misled'' about the police response to the shooting and he's "livid.'' He said exactly what happened needs to be "thoroughly, exhaustively'' investigated.

Questions over time lost

McCraw conceded that standard security protocols advise police to confront an active school shooter without delay.

After shooting his own grandmother, the killer had slammed his Ford pickup into a ditch behind the Texas school 11.28 a.m. He had jumped out carrying an AR-15-style rifle, and entered the halls of Robb Elementary School about 12 minutes later. He then found his way to the fourth-grade classroom where he murdered his victims — children aged between 8 and 11-years-old, as well as two of their teachers.

Police had arrived at the scene at about the same time Ramos entered the school, but were driven back when the gunman opened fire on them.

One individual called the 911 emergency line multiple times starting at 12:03 p.m., telling police in a whisper that there were multiple dead. They said there were still "eight to nine" students alive.

A child had called at 12:47 p.m. and asked the operator to "please send the police now."

Videos emerged on Thursday that showed desperate parents urging police to storm the school, some of them being restrained by police.

Plea for stricter gun laws

Uvalde is the deadliest US school shooting since a gunman killed 26 people, including 20 children, at Sandy Hook Elementary School in Connecticut in December 2012.

Like that massacre, it has prompted calls for a tightening of the US' lenient gun laws. 

Ramos had legally purchased two guns in the days before the attack - an assault rifle from a federally licensed gun dealer on May 17 and a second similar weapon on May 20. He bought them just days after turning 18, the minimum age for buying a rifle under federal law.

Ramos also bought several hundred rounds of ammunition. 

As the National Rifle Association (NRA) started its annual meeting in Houston on Friday, protesters gathered outside to demand an end to the pro-gun lobby's stranglehold on US politics.

rc/rt (AFP, AP, dpa, Reuters)