The police chief who officials say decided to wait to confront the shooter at Robb Elementary School in Uvalde, Texas, completed an active shooter training course in December, law enforcement records show. order.

Uvalde Consolidated Independent School District Police Chief Peter Arredondo completed an eight-hour “Active Shooter Training Mandate” course on Dec. 17, 2021, according to public records from the Texas Commission on Law Enforcement obtained by NBC News. .

He took the same course the previous year, on Aug. 25, 2020, the documents show.

Arredondo, who has been the chief since 2020, prevented at least 19 officers from rushing in as the 18-year-old gunman opened fire for at least an hour, killing 19 students and two teachers, officials said Friday.

“It was the wrong decision,” Steven McCraw, head of the Texas Department of Public Safety, said Friday at a press conference.

McCraw said Arredondo believed the shooter had barricaded himself and the children were not under active threat.

The training course explicitly educates participants on how to “compare/contrast an active fire event and a hostage or barricade crisis”.

Instead of sending officers, he spent time finding keys that would allow him to enter the school, according to McCraw.

Amid the shooting, at least two children called 911, one of whom asked for help; one girl called 911 more than five times, McCraw said.

Local police told federal agents to wait and not enter the school – then decided after about half an hour to ignore that initial advice and find the shooter, two seniors told NBC News on Friday. federal law enforcement officials.

Arredondo was not present Friday when McCraw briefed reporters, and McCraw did not identify him by name.

Arredondo’s cellphone voicemail was full when NBC News attempted to contact him on Saturday. NBC News texted him and also left a message on his work line. The school district did not immediately respond to an email seeking comment, and an after-hours questions phone number appeared to be disconnected.

A policeman stationed outside Arredondo’s home on Saturday said his family refused interviews with reporters.

The Texas Commission on Law Enforcement released the curriculum for the training course two years ago, according to information on the Texas State University Texas School Safety Center website.

Three representatives from the Texas School Safety Center did not immediately respond to an email seeking comment on Saturday, and a spokeswoman for the Texas Commission on Law Enforcement did not immediately respond to a voicemail.

The 30-page training course syllabus is divided into six units.

The first unit aims to teach participants how school shootings over the past decades – including the massacres at Columbine High School in Littleton, Colorado, in 1999, and Marjorie Stoneman Douglas High School in Parkland, Florida, in 2018 – influenced “law enforcement response tactics”. .”

The second unit lays out the “priorities” of response officers and states, “First responders at the active shooter scene will typically need to put themselves in harm’s way and demonstrate uncommon acts of courage to save innocent people. First responders must understand and accept the role of “Protector” and be prepared to confront violence with controlled aggression.”

The third unit is called “Stop the Killing”. The fifth unit is called “Stop the Dying”.

“Time is enemy number one during active shooter response,” the program says. “The short duration and high casualty rates produced by these events require an immediate response to reduce loss of life.”

Records also show that Arredondo completed more generalized school law enforcement training courses on November 12, 2020 and July 18, 2018.

Arredondo recently won a seat on the Uvalde town council, and he is expected to be sworn into the council on Tuesday – exactly a week after the Uvalde shooting.

Arredondo’s older brother Lee, who lives in Uvalde, told an NBC News reporter on Saturday that he felt his brother had been thrown under the bus. Lee Arredondo said the two hadn’t spoken in a few years, but he believes his brother was a “scapegoat”.

“If they want to point a finger at one of them, they have to point a finger at the others too. It’s just not the only police department. There are many who are involved in this, ”said Lee Arredondo.

Lee Arredondo said he has two grown daughters and five grandchildren. He added that one of his daughters told him that there was a lot of animosity towards his brother.

“There’s a lot of hatred towards him – a lot of things are being said,” he said.

Tom Winter, Scott Friedman, Antonio Planas and Safia Samee Ali contributed.