PARKLAND, Fla. - Broward County Sheriff Scott Israel said the shooter at Majory Stoneman Douglas High School in Parkland is in custody.
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According to WPLG Local 10, BSO spokeswoman Keyla Concepcion said the SWAT team was called to the school on Pine Island.
Concepcion said there are reports of victims, but she didn't say how many. Coral Springs Mayor was reported saying that there are "multiple fatalities."
A view from Sky 10 showed at least two people on stretchers. One of them was placed into the back of the ambulance.
Rescuers appeared to be setting up a triage unit in a tent outside the school.
Police and deputies could be seen surrounding the school with their guns drawn.
Students were being guided outside of the school. Some of them had their hands in the air and others were walking out with their hands on each other's shoulders.
It appeared that students were dropping their backpacks in the middle of the street as they were being guided to safety. A crowd of students could be seen sitting on the grass next to the road.
A parent of a ninth-grade student told Local 10 that she was speaking to her daughter via text message.
"She's telling me that she is OK," the woman said. "The teacher has them in the back of the classroom. He locked the door. They know what to do. They're doing the proper procedure, but she's terrified."
The woman said her daughter heard at least one gunshot.
"I'll be relieved when she comes out and I can give her a hug," she said.
Coral Springs police on Twitter were asking students and teachers to remain inside the school until officers can reach them.