Young survivors of last week's school shooting in Florida are determined that the attack will be a turning point in the national gun control debate.
Seventeen students and staff were killed when a former student opened fire at Marjory Stoneman Douglas High School, the deadliest US school shooting since 2012.
Yesterday protesters chanted "shame on you" to US lawmakers and the president.
A number of students are organising a national march on Washington on 24 March, with the hashtag "Never Again" to demand political action on gun laws.
One of the founding members Alfonso Calderon survived the massacre by hiding in a closet with classmates for three hours.
He told Morning Report they wanted to send a message that gun laws in the country needed to change.
"They must change because kids are being slaughtered senselessly. Seventeen of my friends were killed because of the NRA (National Rifle Association) and people who think that more guns are going to help."
Listen to Susie Ferguson's full 15 minute interview with shooting witness Alfonso Calderon who hid in a closet with classmates for three hours
The suspected gunman, Nikolas Cruz, 19, has admitted the attack.
Mr Calderon said Cruz was troubled in every way imaginable and had been reported to the police 39 times since 2010, as well as having been expelled from school.
"He was still completely able to just go to the gun store, show them his ID and buy an assault rifle. He bought an AR-15. It's just unacceptable."
"I can't even begin to describe how much it saddens me that great people lost their lives because the government and the politicians didn't care enough.
"They didn't care enough to enact sensible gun laws, they didn't care enough to pass screenings strict enough so that someone who is clearly mentally ill, who is clearly unable to wield a semi-automatic weapon, an AR-15, a weapon of war, a military grade weapon - it's truly heart-breaking," Mr Calderon said.
"I really hope that President Donald Trump has the courage, and Marco Rubio and Rick Scott, and every single politician in this country taking money from the NRA, to come and talk to us, one-on-one and tell us that they personally believe that sensible gun laws are in place.
"In Florida alone there was the Orlando Pulse nightclub shooting, there was the Fort Lauderdale airport shooting, and now there's us. It doesn't get more obvious."
Trump blames Democrats for inaction on gun laws
Mr Trump last year he would "never" infringe on the right to keep arms - a long-running and contested debate within the US.
In his first public comments on the gun control issue since the attack, Mr Trump blamed the Democrats for not passing legislation when they controlled Congress during the early years of Barack Obama's administration.
He also rebuked the FBI for missing signals before Wednesday's school shooting, after the organisation admitted it had failed to act on a tip-off about the suspected shooter Nikolas Cruz.
What are the students plans?
Speaking on US television networks on Sunday morning, student survivors from Marjory Stoneman Douglas announced their March for Our Lives campaign.
They are planning to march on Washington on 24 March to demand that children and their families "become a priority" to US lawmakers. They want other protests to happen simultaneously in other cities on the same day.
"We are losing our lives while the adults are playing around," Cameron Kasky, a survivor from the school said.
It is one of many student-led protests amassing support on social media in the wake of Wednesday's attack.
On Saturday students and their parents - as well as politicians - took part in an emotionally-charged rally in Fort Lauderdale, close to Parkland.
Arguably the most memorable moment came when high school student Emma Gonzalez took to the podium and attacked the US president and other politicians for accepting political donations from the National Rifle Association (NRA), a powerful gun rights lobby group.
"If the president wants to come up to me and tell me to my face that it was a terrible tragedy and ... how nothing is going to be done about it, I'm going to happily ask him how much money he received from the National Rifle Association," Ms Gonzalez said.
"It doesn't matter because I already know. $US30 million," the 18-year-old said, referring to donations during Mr Trump's presidential campaign.
"To every politician who is taking donations from the NRA - shame on you!" Ms Gonzalez said, who took cover on the floor of her secondary school's auditorium during the attack.
According to the Center for Responsive Politics, the NRA spent $US11.4m supporting Mr Trump in the 2016 campaign, and $US19.7m opposing Hillary Clinton.
What is Mr Trump's stance on gun control?
The president's views on gun control have shifted over time. In recent years, he has pledged to fiercely defend the Second Amendment to the US Constitution, which protects people's right to keep and bear arms.
Last year, he told an NRA convention he would "never, ever infringe" on that right.
In a tweet late on Saturday, the Republican president accused the Democrats of not acting on gun legislation "when they had both the House & Senate during the Obama Administration.
"Because they didn't want to, and now they just talk!" he wrote, referring to criticism from Democrats following Wednesday's shooting.
Mr Trump - who on Friday met survivors of the attack - has also blamed the shooter's mental health and the FBI's failings.
US news network CNN has invited Florida lawmakers and the president to attend a town hall event with survivors of the attack on Wednesday.
Saturday's rally coincided with a gun show in Florida. Hundreds of people attended the event at the Dade County fairgrounds, despite calls to cancel it.
What do we know about the suspect?
Mr Cruz, 19, is a former student at the Marjory Stoneman Douglas High School.
He was reportedly investigated by local police and the Department of Children and Family Services in 2016 after posting evidence of self-harm on the Snapchat app, according to the latest US media reports.
Child services said he had planned to buy a gun, but authorities determined he was already receiving adequate support, the reports say.
The reports come after the Federal Bureau of Investigation (FBI) admitted it did not properly follow up on a tip-off about Mr Cruz last month.
The 5 January tip was not the only information the FBI received. In September, a Mississippi man reported to the law enforcement agency a disturbing comment left on a YouTube video under Mr Cruz's name.
Florida Governor Rick Scott called for FBI director Christopher Wray to resign over the failures to act.
In a late tweet on Saturday, the President rebuked the organisation for their handling of tip-offs.
"Very sad that the FBI missed all of the many signals sent out by the Florida school shooter. This is not acceptable. They are spending too much time trying to prove Russian collusion with the Trump campaign."