US students have walked out of classrooms across the US to demand tighter gun safety laws, joining a movement spearheaded by student survivors from the Florida high school where a gunman killed 17 people last month.
The #ENOUGH National School Walkout, began at 10am local time (1am AEDT) on Wednesday across the country, and lasted 17 minutes, commemorating the 17 students and staff killed at Marjory Stoneman Douglas High School in Parkland, Florida on February 14.
The walkout is part of a burgeoning, grassroots movement that grew out of the Parkland attack.
Some of the survivors have lobbied state and federal politicians, and even met with US President Donald Trump, to call for new restrictions on gun ownership, a right protected by the Second Amendment of the US Constitution.
"If our elected officials don't take responsibility for their inaction on both sides of the aisle, then we are going to kick them out of office," David Hogg, a Stoneman Douglas student, said in an interview with MSNBC on Wednesday.
Hundreds of students from the Washington area are rallied at the Capitol.
House Democratic Leader Nancy Pelosi and other politicians addressed the crowd.
The biggest applause by far was for Vermont Sen. Bernie Sanders.
Students chanted his name and nearly drowned out his speech.
Students from more than 2800 schools and groups participated in the walkout, many with the backing of their school districts, according to the walkout's organisers, who also co-ordinated the Women's March protests staged nationwide over the past two years.
Support has also come from the American Civil Liberties Union and Viacom Inc, which said all seven of its networks, including MTV, which suspended programming at 10am in each US time zone during the 17-minute walkout.
But a few school districts around the country have warned against protests during school hours.
Administrators in Sayreville, New Jersey, told students that anyone who walked out of class would face suspension or other punishment, according to myCentralJersey.com.
The New York City Department of Education said it would allow students to participate if they submitted a signed permission slip from their parents. It would consider the walkout an excused absence.
A student at Kell High School outside Atlanta says the principal there had threatened students with discipline and said they could be in danger since the time of the nationwide protest was widely known and someone could try to harm them outside the school.
Kirsten Martin said students were scared of the potential punishment, so at 10am "we just carried on like it's a normal day."
Despite the threat, three students at the Marietta, Georgia, school walked out for the 17 minutes of the protest and then went back inside.
At some schools, students didn't walk outside, but instead lined the hallways, standing in silence and wearing the school colors of Marjory Stoneman Douglas High School, which was the site of last month's mass shooting that killed 17 people.
Others gathered in school gyms and auditorium.
In Newtown, Pennsylvania, Council Rock School District will designate an area inside schools where students could gather in a "non-political fashion" to remember the shooting victims. Officials will block all entrance and exit points for the duration of the protest to prevent students from walking out.
More than 40 US colleges and universities, including Yale, Brown and the Massachusetts Institute of Technology, have said their admissions offices would not penalise any applicants who may be disciplined for protesting.
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