(NewsNation) — Surveillance video footage from inside Robb Elementary School, published by the Austin American Statesman, shows gunman Salvador Ramos entering the building, clad in body armor and armed with an assault rifle, before he massacred 21 people inside the school.

The 77 minutes of footage also shows police officers standing in a hallway outside of the classroom where Ramos was murdering children, for nearly an hour before they finally entered the unlocked classroom and killed Ramos.

Officers, many of whom were heavily armed and armored, have been heavily criticized for not entering the classroom sooner and the footage paints a clear picture of the officer’s painstakingly slow action during the shooting.

Texas Gov. Greg Abbott’s office said in a statement he was “disheartened” by the release of the video before the families of victims had a chance to see it.

“The Governor has been clear since day one that he expects all information surrounding the tragedy at Robb School Elementary to be released, and we do appreciate that the Uvalde community is getting answers,” the statement read. “The investigations being conducted by the Texas Rangers and the FBI are ongoing, and we look forward to the full results being shared with the victims’ families and the public, who deserve the full truth of what happened that tragic day.”

Uvalde Mayor Don McLaughlin was similarly upset with the footage being released.

“This has been the most unprofessional investigation or handling of it that I’ve ever seen in my life,” McLaughlin said in an interview with The Associated Press. “These families get blindsided constantly.”

Hours after the video was published, some residents at a Uvalde City Council meeting said they had not been able to bring themselves to watch it.

Jesus Rizo said officers who are paid taxpayer dollars to protect people should not have “sat there” when children were in danger.

“You could’ve saved some lives. You could have held somebody’s hand as they were dying,” he said. “The parents could have seen them one last time as they were dying.”

Others demanded consequences for police and more information in an investigation marked by confusing statements that have had to be retracted at times.

“Give these families some closure,” said Daniel Myers, a pastor in Uvalde and family friend to one of the victims.

The first three officers who entered the hallway Ramos was in can be seen approaching the classroom he was shooting in, before quickly fleeing the area when gunfire was directed at them.

Uvalde School Police Chief Pete Arredondo, the commander of the police response that day, treated the incident as a barricaded subject rather than an active shooter, sparking the slow police response, said Texas Department of Public Safety Director Steve McCraw.

Arredondo however, claims he did not believe he was in charge that day and says he did not even have his police radio with him during the shooting, he told the Texas Tribune.

Arredondo resigned from his position on the Uvalde City Council last week. On Tuesday night the Uvalde City Council unanimously accepted Arredondo’s resignation. A special election will be held to replace him.

Rep. Dustin Burrows, a Republican leading an investigation into the shooting, tweeted that the video and findings from a preliminary report will be shown Sunday in Uvalde to residents and distributed publicly soon after.

“We feel strongly that members of the Uvalde community should have the opportunity to see the video and hear from us before they are made public,” Burrows tweeted.

Burrows said his committee has interviewed more than 40 people behind closed doors over the last several weeks, including law enforcement who were at the scene. He has defended the committee talking with witnesses in private to elicit more candor about what happened.