Watch: 'President Trump, please do something' – mother of school girl gunned down by Florida shooter pleads for action

The mother of a 14-year-old girl killed in yesterday's Florida school shooting has made an angry, emotional plea urging President Trump to instil new gun safety measures to protect children. 

Speaking on CNN Lori Alhadeff, whose daughter Alyssa was shot to death, talked directly down the camera.

"How? How do we allow a gunman to come into our children's school?" 

Seventeen people died after Nikolas Cruz, 19, stormed into the school with an AR-15, shooting students and teachers yesterday. He confessed to investigators today. 

Ms Alhadeff called for better security in schools, includinginstalling metal detectors at entrances.

"The gunman, a crazy person, just walks right into the school, knocks down the window of my child's door, and starts shooting, shooting her and killing her.

"President Trump, you say, 'What can you do?'," Ms Alhadeff shouted.

"You can stop the guns from getting into these children's hands. What can you do? You can do a lot."

She said she had just spent two hours making burial arrangements for her daughter. 

"President Trump, please do something. Action. We need it now. These kids need safety now."