'It's a Bad Day, Shepard': Sen. Bill Nelson Reacts to Florida School Shooting

DEVELOPING: More Than 20 Victims Reported in Florida High School Shooting

Broward County Schools Superintendent Robert Runcie said there were "numerous fatalities" following a Wednesday shooting at Marjory Stoneman Douglas High School.

"It's just a horrible day for us," Runcie said. "It's a day that you pray every day... that you will never have to see."

Runcie asked the community for prayers, saying Floridians and Americans "cannot live in a world built on fear."

He called for further focus on mental health issues following the shooting, saying there was "no warning" before a male opened fire at the school around 3 p.m.

Later Wednesday, Broward County Sheriff Scott Israel said the suspect is a former student at the school.

Parkland is north of Miami, near Pompano Beach.

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