AS the death toll from the latest US school shooting mounted, Phil Mudd's anger, and grief, was palpable.
The CNN counter-terrorism expert is a veteran of the CIA and the FBI. But the school shooting broke him. Choked up, angry, and frustrated, he fought tears as he struggled to talk about it, ultimately breaking down on air.
"I have 10 nieces and nephews," he told CNN's Wolf Blitzer, his voice breaking, and anger rising.
"We're talking about bump-stocks. We're talking about legislation.
"A child of god is dead. Cannot we acknowledge in this country that we cannot accept this?
"I can't do it Wolf. I'm sorry. I can't do it!" Mudd cried, choking up and looking away from the camera."
At that point, Blitzer mercifully cut away.
"OUR F*****G SCHOOL IS GETTING SHOT UP"
Meanwhile horrifying footage has emerged from inside a classroom during the latest US school mass shooting.
"Holy s**t, holy s**t ... oh my God," screams Facebook user Matt Walker repeatedly as rapid-fire gunshots ring out in the Florida high school.
Students curl on the ground, cowering under chairs and tables in terror in their classroom.
Wails and screams of fear punctuate a short pause in the gunfire, before the volley of shots begins again.
There's a brief silence. Then more screams. And again, more gunfire.
"Our f***ing school is a getting shot up," is the caption on the terrifying footage.
Horrifying Video From Inside Classroom During Florida School Shooting— Breaking911 (@Breaking911) February 14, 2018
WARNING: GRAPHIC CONTENT pic.twitter.com/EtvsxYPvgh
The student who captured the video was one of a number of terrified teens caught up in the horror mass shooting at Marjory Stoneman Douglas High School, who used their mobile phones to chronicle the horror on social media as the attack continued.
In another video, muffled cries of fear, and demands of "put your phones away" have been relayed to the world as students mutely raising their hands in the air and a fully-armed SWAT team enters their classroom to clear it following the deadly rampage.
RAW VIDEO: SWAT Team Clears Classroom Following Deadly School Shooting In Florida pic.twitter.com/ARYekZI17p— Breaking911 (@Breaking911) February 14, 2018
At least 17 people have died after former student Nikolas Cruz opened fire in the school.
It's believed to be the ninth deadliest shooting in US history and the death toll is expected to rise.
Eyewitness accounts revealed the full horror of the attack.
A teacher was killed trying to save his students, one student, Alex, told WSVN 7 News.
They had tried to leave their classroom, but returned after hearing gunfire nearby.
As her teacher tried to close the door and lock them in, "he was actually shot and killed, right there," Alex said.
"The door was left open the whole time, and as he [the shooter] walked by the door was open. He could have walked in at any time.
"We just had to be as quiet as possible."
WATCH: Student witness says teacher was killed trying to save students— Breaking911 (@Breaking911) February 14, 2018
Many students recorded pictures and videos as they waited in hope for help to arrive.
Still locked in. I checked the local news and there is 20 victims. Long live Majory Stoneman Douglas High. pic.twitter.com/4kQMAlCBWt— Aidan (@TheCaptainAidan) February 14, 2018
18 SHOOTINGS THIS YEAR ... AND IT'S FEBRUARY
As the death toll mounted, the US again grappled with anger, frustration, and its eternal debate over gun control.
The Valentine's Day school gun rampage brought to 18 the number of school shootings across the United States so far this year, AFP reports.
The number underscores how commonplace gun violence has become in America, where school students regularly performing drills on how to react in an "active shooter" situation.
According to the independent Everytown for Gun Safety group, eight of the 18 school shooting incidents so far this year, which cover primary schools to universities, involved guns being discharged with no one injured.
Two were suicide attempts, and the rest attacks on others.
This attack is the worst so far in 2018.
On January 23, a 15-year-old boy opened fire with a handgun at the start of the school day at a Kentucky high school, killing two students and wounding others.
The day before, a teenager was wounded by a shot fired in her school cafeteria in Texas. The same day, a bullet grazed a 14-year-old boy in the parking lot of a New Orleans high school.
Earlier in January, shootings took place in Iowa, Washington state and California, among other places.
The frequency of the incidents has somewhat dulled their ability to shock. The nation was stunned on December 14, 2012 when Adam Lanza, 20, shot dead 20 schoolchildren and six teachers at Sandy Hook Elementary School in Newtown, Connecticut.
Since January 2013, there have been at least 291 school shootings, according to Everytown for Gun Safety, a non-profit group that advocates for gun control.
"Are we coming to expect these mass shootings as a kind of routine matter?" Florida Senator Bill Nelson told CNN.
Each incident like the one in Parkland brings calls for more strict laws on gun sales and ownership, but gun rights campaigners regularly succeed in stifling those calls.
Indeed, laws on carrying guns in public have been made less strict in many areas.
"If more guns and fewer gun laws made us safer, we wouldn't have the highest rate of gun violence among peer nations," Shannon Watts, founder of Moms Demand Action for Gun Sense in America, said on Twitter.seb/pmh/sst
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