The Broward Sheriff’s Office revealed Wednesday that the alleged shooter at Marjory Stoneman Douglas High School tried to flee by hiding himself among the students exiting the building.
Authorities allege Nikolas Cruz, 19, “concealed himself in the crowd and was among those running out of the school.”
Investigators had to comb through security footage to identify Cruz, which led to his arrest in a nearby neighborhood of Coral Springs, Fla., the Sheriff’s Office said in a statement. He was a former student of the school who was expelled due to disciplinary reasons.
Cruz showed signs of having difficulty breathing and was transported to Broward Health North hospital, according to Broward County Sheriff Scott Israel.
“I don’t think his injuries were anything significant,” he said, adding that Cruz had been released to police custody. He said 17 people were killed in the mass shooting on Wednesday afternoon.
Of those 17, he said 12 people were killed within the school, two people were killed outside of the building, one person was killed on a nearby street corner and two people died in the hospital.
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Israel said officials have begun to “dissect” social media sites related to the suspect, and that “some of the things that have come to mind are very disturbing.”
Lissette Rozenblatt, 49, a mom whose daughter is a sophomore at the school, told PEOPLE, “She kept texting me and she kept saying she was fine and she was hiding. She told me to please call the police because somebody was hurt, and she kept hearing that person crying out for help.”
Parkland is a Fort Lauderdale suburb of about 30,000 people. The school has an enrollment of 3,208, according to the Broward County Public Schools website.
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Florida Senator Bill Nelson told CNN, “It’s a bad day for Florida and for the country.”
Nelson added, “How many of these have we had? Are we coming to expect these mass shootings to be a routine kind of matters and after everyone we say enough is enough? And then it continues to happen.”