At least 17 dead in Florida school shooting

'EVERYONE STARTED RUNNING'

Student Jeiella Dodoo told CBS News that she and her schoolmates had evacuated their classroom calmly after hearing what they thought had been a routine fire alarm.

"The alarm went off so we had to evacuate from our classes," she said. "Then we heard gunshots.

"I heard about six gunshots," she said, "and then some people started running and then everyone started running because we were like 'If it's real, then just run.'"

A math teacher at the school told CBS that he was hiding with six of his students. "We are fine. We are waiting," he said.

Caesar Figueroa told CNN his daughter was hiding in a closet and texting her family.

"She's trapped with her 10 friends. She said she heard gunshots. A window blew and everybody is screaming and running, and she said she ran in the closet and she's still there," Figueroa said.

NO CHILD SHOULD 'FEEL UNSAFE'

"My prayers and condolences to the families of the victims of the terrible Florida shooting," President Donald Trump said on Twitter.

"No child, teacher or anyone else should ever feel unsafe in an American school."

My prayers and condolences to the families of the victims of the terrible Florida shooting. No child, teacher or anyone else should ever feel unsafe in an American school.

— Donald J. Trump (@realDonaldTrump) February 14, 2018

Since January 2013, "there have been at least 283 school shootings across the country - which averages out to one school shooting a week," according to Everytown for Gun Safety, a non-profit group that advocates for gun control.

Since the 2012 massacre at the Sandy Hook Elementary School in Newtown, Connecticut, where 20 children and six adults were shot dead, warning procedures and emergency drills have multiplied at US schools.

The goal is to teach school children how to react to a shooter who opens fire at random.