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TOPSHOT - Marjory Stoneman Douglas High School staff, teachers and students return to school greeted by police and well wishers in Parkland, Florida on February 28, 2018. 
Students grieving for slain classmates prepared for an emotional return Wednesday to their Florida high school, where a mass shooting shocked the nation and led teen survivors to spur a growing movement to tighten America's gun laws. The community of Parkland, Florida, where residents were plunged into tragedy two weeks ago, steeled itself for the resumption of classes at Marjory Stoneman Douglas High School, where nearby flower-draped memorials and 17 white crosses pay tribute to the 14 students and three staff members who were murdered by a former student.
 / AFP PHOTO / RHONA WISE        (Photo credit should read RHONA WISE/AFP/Getty Images)
RHONA WISE/AFP/AFP/Getty Images
TOPSHOT - Marjory Stoneman Douglas High School staff, teachers and students return to school greeted by police and well wishers in Parkland, Florida on February 28, 2018. Students grieving for slain classmates prepared for an emotional return Wednesday to their Florida high school, where a mass shooting shocked the nation and led teen survivors to spur a growing movement to tighten America's gun laws. The community of Parkland, Florida, where residents were plunged into tragedy two weeks ago, steeled itself for the resumption of classes at Marjory Stoneman Douglas High School, where nearby flower-draped memorials and 17 white crosses pay tribute to the 14 students and three staff members who were murdered by a former student. / AFP PHOTO / RHONA WISE (Photo credit should read RHONA WISE/AFP/Getty Images)
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This image made available by the Broward County Sheriff's Office on Sunday, Feb. 18, 2018, shows Sheriff Scott Israel, holding the hand of Anthony Borges, 15, a student at Marjory Stoneman Douglas High School. The teenager was shot five times during the massacre on Valentine's Day that killed 17 students. Borges is being credited with saving the lives of at least 20 other students. (Broward County Sheriff's Office via AP)
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This image made available by the Broward County Sheriff's Office on Sunday, Feb. 18, 2018, shows Sheriff Scott Israel, holding the hand of Anthony Borges, 15, a student at Marjory Stoneman Douglas High School. The teenager was shot five times during the massacre on Valentine's Day that killed 17 students. Borges is being credited with saving the lives of at least 20 other students. (Broward County Sheriff's Office via AP)
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(CNN) —  

A student who witnessed Wednesday’s massacre at a Florida school made a direct plea to lawmakers on Thursday to take action, warning more children will die otherwise.

“Some of our policymakers and some people need to – they need to look in the mirror and take some action because ideas are great but without action, ideas stay ideas and children die,” Marjory Stoneman Douglas High School senior David Hogg told CNN’s “New Day.”

At least 17 people were killed Wednesday afternoon when, authorities say, a 19-year-old former student opened fire at the Parkland school near Fort Lauderdale. Nikolas Cruz has been charged with 17 counts of premeditated murder, the Broward County Sheriff’s Office said.

Florida school shooting: Live updates

Hogg, who is a student journalist, recorded footage of the shooting, but “New Day” anchor Alisyn Camerota explained that it can’t be shown on air because of its graphic nature.

Hogg detailed why he recorded what was happening.

“I was really thinking about, ‘What has my impact been? What have any of our impacts been?’ … I thought to myself, ‘If I die today, I want my impact to be – if I die I want to tell a good story,’ ” he said.

“I want to show these people exactly what’s going on when these children are facing bullets flying through classrooms and students are dying trying to get an education. That’s not OK, and that’s not acceptable and we need to fix that.”

The student said his younger sister lost two of her best friends in the shooting.

He looked directly into the camera as he called on lawmakers: “We’re children. You guys are the adults. You need to take some action and play a role. Work together, come over your politics, and get something done.”

Moments later, US Rep. Ted Deutch, D-Florida, joined Camerota on “New Day” and revealed that Hogg was serious about delivering his message to elected officials, on and off-camera.

“I appreciate the interview that you just did with the two students,” Deutch said, referring to Hogg and his schoolmate Kelsey Friend.

“When they were leaving, I went to tell them how brave I thought they were, and (Hogg) looked at me and he said, ‘We want action.’ “