The United States were in shock on Tuesday following the senseless shooting that took place at a primary school in Uvalde, Texas.
MORE: Celebrities speak out on tragic Texas school shooting - from Kourtney Kardashian to Amy Schumer
ABC News were among the outlets to first break the news, with David Muir reporting on the horrific incident, understandably close to tears.
The news clip was shared on Good Morning America's Instagram account, and viewers left a mass of heartbreaking responses to the tragedy.
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"Another breaking news story, another school, another town, more victims who did nothing for this to happen and nothing is being done to change it!!" one wrote, while another commented: "This is so heartbreaking." A third added: "When will it stop? Those poor parents."
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On Tuesday, 19 children and two adults were killed by a lone gunman. The 18-year-old suspect opened fire at Robb Elementary School in Uvalde where children aged seven to 10 were being taught.
The teenage suspect had a handgun, an AR-15 semi-automatic rifle and high-capacity magazines, according to investigators.
David Muir had a heartbreaking job to do on Tuesday as he repoted on the Texas shooting
He was killed by law enforcement after his attack. Many public figures have spoken out on the senseless crime in the aftermath of the event.
MORE: Robin Roberts delivers 'painful and difficult' message in wake of Texas shooting
President Joe Biden delivered an emotional speech alongside his wife, Jill Biden. "As a nation, we have to ask, 'When in God’s name are we going to stand up to the gun lobby? When in God's name are we going to do what has to be done? Why are we willing to live with this carnage?"
He was "sick and tired of it", he said, adding: "We have to act."
Flags will be flown at half-mast until sunset on Saturday in observance of the tragedy, Joe added.
Joe Biden also spoke out on the senseless shooting
Celebrities from Texas have also spoken out. Matthew McConaughey, who is from Uvalde, penned an agonizing message on Instagram discussing the senseless act.
"Once again, we have tragically proven that we are failing to be responsible for the rights our freedoms grant us," he wrote, in part.
"The true call to action now is for every American to take a longer and deeper look in the mirror and ask ourselves, 'What is it that we truly value? How do we repair the problem?'
"We cannot exhale once again, make excuses, and accept these tragic realities as the status quo."
David often reports on hard-hitting headlines
He went on to ask Americans to find "common ground" so that they can put an end to mass shootings.
"And to those who dropped off their loved ones today not knowing it was goodbye, no words can comprehend or heal your loss, but if prayers can provide comfort, we'll keep them coming."
Selena Gomez, who is from Texas, also spoke out. "Today in my home state of Texas 18 innocent students were killed while simply trying to get an education," she wrote ahead of the updated figure.
"A teacher killed doing her job; an invaluable yet sadly under appreciated job. If children aren't safe at school where are they safe?"
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