Seventeen people were killed and at least a dozen more injured on Wednesday in a mass shooting at a high school in southeast Florida, officials said.
The Broward County Sheriff's Office on Wednesday night identified the shooter as Nikolas Cruz, a 19-year-old former student. CNN reported that Cruz was equipped with an AR-15 assault rifle, multiple ammunition magazines, gas mask and smoke grenades. He reportedly pulled a fire alarm at the end of the school day in an effort to increase the death toll from his attack.
Cruz was quickly arrested without incident in nearby Coral Springs after the shooting at Marjory Stoneman Douglas High School in Parkland, a suburb of Fort Lauderdale, the Los Angeles Times reported.
"It's catastrophic," Broward County Sheriff Scott Israel told reporters at a news conference. "There really are no words."
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Cruz may have been identified previously as a potential threat to fellow students, according to one teacher, the Miami Herald reported. Multiple reports indicate he was expelled from the school.
Earlier on Wednesday, the office said on Twitter that the victims were taken to Broward Health Medical Center and Broward Health North Hospital.
The sheriff's office also tweeted that the shooter was in custody and local TV footage showed officers putting a man into a police car outside the school.
"All of a sudden I heard, 'Boom, boom, boom!' and I heard screaming everywhere. We fell underneath my teacher's desk. The shooter was literally feet outside of my classroom," Michael Katz, a student at the high school, told ABC News.
Israel said SWAT teams are continuing their efforts to clear the school.
For continuing coverage of the school shooting, the Palm Beach Post is providing live updates.
The Broward County Sheriff's Office is also tweeting regularly on the situation.
WFOR-TV in Miami is providing live video coverage.