"He used to sell knives out of his lunchbox, which I thought was like insane because you can't have knives".
"At no time was any Secret Service protectee in danger or impacted", it said in a statement.
Originally meant to include just 17 students - one to represent each person killed during the shooting at Marjory Stoneman Douglas High School in Parkland, Florida - the demonstration grew to include over one hundred.
The driver said he had forgotten to leave the weapon in his auto, the report said.
Federal law enforcement officials say Trump's posting misstates how the FBI actually works.
Prior to being elected, Trump earned the support of the National Rifle Association.
"I still can't process it because this isn't the person we knew", Kimberly Snead continued.
The demonstration was organized by Teens For Gun Reform, an organization created by students in the Washington, D.C., area in the wake of Wednesday's shooting at Marjory Stoneman Douglas High School in Parkland, Fla.
Trump orders ban on 'bump stock' gun modifications
Republicans including President Trump have said that warning signs had been ignored by those around Cruz before the outburst of violence, though the Federal Bureau of Investigation admitted late last week that it failed to properly investigate a tip from last month about him carrying out a potential school shooting.
Meanwhile, organisers behind anti-Trump and female empowerment protest the Women's March called for a 17-minute, nationwide walkout by teachers and students on March 14.
CNN is holding a town hall meeting on Wednesday with the victims' classmates, parents, community members, and some Florida politicians. Between 2011 and 2016, Broward County sheriff deputies were called to Cruz's mother's home 39 times, several of them allegedly due to Cruz's violent outbursts.
"This is a listening session to see what can be done better, what the actual concerns of the students are, what they would like to see", Sanders said.
"We didn't know he had such an evil past", Mr. Snead told the NYT.
But hours later, the Sneads heard of shooting reports and called their son who attended the high school - he was already fleeing the scene.
In September, Nikolas Cruz, using a screen name on YouTube of "Nikolas Cruz", wrote "I'm going to be a professional school shooter".
"The "lie-in" itself was powerful, and we are so appreciative of the protesters, friends and media who came", Bowen said.
"I was just furious and heartbroken", Kimberly Snead said. "And it never should have happened".