Horrific Florida School Shooting: No Less Than 17 Dead And Other Victims in Life Threatening Condition [See Photos]

A gunman opened fire at a South Florida high school today, killing 17 people and sending students running for their lives, according to two law enforcement officers on the scene.

At least 14 victims were being treated by Broward Health Hospitals from the incident at Stoneman Douglas High School in Parkland; five are in life-threatening condition. Victims include students and adults, the Broward Sheriff's Office said.

-- The suspect, 19-year-old Nikolas Cruz, was taken into custody off campus. He slipped out of the school after the shooting by blending in with other students who were trying to escape, according to two law enforcement sources and an eyewitness.

-- Cruz had "countless magazines" and was believed to have an AR-15 rifle, the sheriff said.

-- The sheriff said Cruz had attended the school but was expelled for disciplinary reasons.

-- Students were seen sprinting out of the school with their hands up as authorities with guns drawn swarmed the area. Other students were seen lined up one by one, leaving the area in an orderly fashion. Some students were hysterical.

Student Michael Katz told ABC News that at the end of the day he "heard what sounded like a garbage truck like banging."

"Then also I hear, 'Boom, boom, boom.' I hear screaming everywhere," he said. "I just got underneath my teacher's desk."

"We had police invade the school, and we were taken out," Katz said. "Fortunately, my father was there to pick me up."

One mother shaking with worry told WPLG her daughter said she was OK, huddled in a locked classroom.

"She's terrified," the mother said. "I'm glad that she's able to text."

Still locked in. I checked the local news and there is 20 victims. Long live Majory Stoneman Douglas High. pic.twitter.com/4kQMAlCBWt

— Aj22000 (@TheCaptainAidan) February 14, 2018

Freshman student Samuel Dykes told the Orlando Sentinel that he was on the third floor of the school when he heard gunshots.

Officers told students to look forward as they evacuated, but Dykes told the newspaper that he saw several bodies in a classroom.

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