The move to publish video caps a weekend spat over how to handle the footage.
UVALDE, Texas -- Two Texas news outlets have published disturbing surveillance video from inside Robb Elementary School during the May 24 mass shooting, as Uvalde officials and families debate the sensitive footage's release.
"Both media outlets have elected to release that footage Tuesday to provide transparency to the community, showing what happened as officials waited to enter that classroom," KVUE stated in its article on the footage, which shows the gunman walking into the school building and officers responding three minutes later.
The edited surveillance footage shows dozens of law enforcement officers, including some with protective shields, waiting in the hallway. Officers didn't breach the classroom for more than 70 minutes, even as four additional shots were fired from the classrooms 45 minutes after police arrived on the scene, the footage released by the news organizations shows.
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The release comes hours after a key state lawmaker in Texas vowed Tuesday to release surveillance video from inside the school, a move he says is intended to provide transparency to the families of the 21 victims despite guidance from the local district attorney that the footage remain under wraps.
Rep. Dustin Burrows, the chairman of a special Texas House panel investigating the school shooting, tweeted early Tuesday that his committee planned to meet with members of the Uvalde community this coming Sunday to "provide them an opportunity to see the hallway video and discuss our preliminary report."
"Very soon thereafter, we will release both to the public," Burrows added.
In the wake of the reporting from KVUE and the Austin American-Statesman on Tuesday, Burrows expressed his disappointment at the release of the footage.
"The committee is aware a portion of the hallway video has been made public. While I am glad that a small portion is now available for the public, I do believe watching the entire segment of law enforcement's response, or lack thereof, is also important," he wrote on Twitter. "I am also disappointed the victim's families and the Uvalde community's requests to watch the video first, and not have certain images and audio of the violence, were not achieved."
Burrows' pledge to release the video and its partial release by the news organizations cap a dizzying weekend spat among state officials, law enforcement agencies and Uvalde's mayor about how to handle sensitive investigative materials, including hallway surveillance footage purportedly showing the police response to the shooting.
Officials with the Texas Department of Public Safety have expressed tepid support for releasing the hallway footage, but say they have resisted doing so at the urging of Uvalde-area District Attorney Christina Busbee, whose investigation into the shooting remains ongoing. Busbee has not responded to requests for comment from ABC News.
Late Monday, Texas Gov. Greg Abbott, who is running for reelection, joined Burrows and Uvalde's mayor, Don McLaughlin, in calling for the footage to be made public.
In a statement obtained Tuesday by KVUE, Abbott's office said the governor "is disheartened and disappointed that this video was leaked before the victims' families and the Uvalde community -- those most affected by this tragedy -- had the opportunity to view 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," it continued. "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."
While in favor of its release, McLaughlin expressed anger Tuesday that the footage was leaked ahead of Sunday's meeting, saying that families were "blindsided."
"They need to see the video, but they don't need to see the gunman going in there. They don't need to listen to those gunshots. They know what happened in that classroom. Why put them through that?" he told ABC News. "And half of these families are out of town right now in Washington, D.C., not even with the rest of their family [...] I'm sorry. That's wrong. These families were blindsided and it shouldn't have been done this way."
Families of children who were killed in the massacre also spoke out in anger, demanding answers for the leak.
"They weren't supposed to do it without our consent," Javier Cazares, the father of 9-year-old Jacklyn Cazares, said during a press briefing Tuesday night.
Several of the families who were meeting with lawmakers hours before in Washington, D.C., said they had not seen the video -- despite repeated requests.
"We've been asking the DA for this video for a while and she refused to let us see it," Nikki Cross, the mother of 10-year-old Uziyah Garcia, said. "So once again, the world got to see it before us."
Kimberly Mata-Rubio, the mother of 10-year-old Alexandria Aniyah Rubio, said families didn't want the video published until they were able to view it on Sunday.
"We understand that the media -- it wants to hold people accountable because the government hasn't been transparent with us," Mata-Rubio said. "You don't need the audio for that."
"We have to tell our family back home to not watch the news," she added. "It's unacceptable."
The confusion over the video's release has exacerbated frustration within the Uvalde community and among family members of the victims, who have criticized law enforcement for their response to the shooting and subsequent handling of the investigation. Texas Department of Public Safety Director Steve McCraw characterized the police response as "an abject failure" during testimony before a Texas Senate panel last month.
McCraw reiterated that assessment on Tuesday while also saying he was "deeply disappointed" at the video's release before all impacted families could view it.
"Those most affected should have been among the first to see it," he said in a statement. "As I stated during my testimony before the Senate Special Committee to Protect All Texans, this video provides horrifying evidence that the law enforcement response to the attack at Robb Elementary on May 24 was an abject failure."
McCraw and his agency have also faced scrutiny for releasing incorrect or, at times, contradictory information about the police response.
Seven weeks after the shooting, numerous questions remain about the 77 minutes that elapsed between the time the shooter entered the school and the moment law enforcement officers breached a classroom and killed him.
Families of the victims say they hope the surveillance footage provides some clarity.
ABC News' Laura Romero and Soo Rin Kim contributed to this report.