FORT LAUDERALE (CBSMiami) – As Fort Lauderdale police officers descended on the campus of Calvary Christian Academy on Monday afternoon, parents gathered nearby to share their fears and concerns.
"We were over there for an hour and a half not knowing what was going on," said parent Valdecir DeSouza. "It was terrible for us."
"You're so vulnerable," said parent Patrick Lima. "You've got no control. You're so helpless."
Many parents prayed as their fears ran rampant especially in light of Sunday's deadly shooting at a Texas church.
"You never know these days with people having guns and the availability to your children," said Bianca Whiting.
Meanwhile inside the school, children huddled in classrooms as teachers draped black cloths over windows and tried to reassure their students during the lockdown.
"They told us to pray and stay calm," said Gabriella Lima.
"I was really scared because it's a life or death situation,' said Annabelle DeSouza.
Later, police gave the all clear. They opened the gates and parents poured in to finally find and embrace their kids.
CBS4 News learned that the alert of an armed intruder on campus came from an app — School Guard — used by staff at Calvary Chirstian.
Nate McVicker, owner and creator of School Guard, said School Guard aims to put a panic button on the smartphone of approved school staff members, which instantly notifies other staff, 911 and nearby police officers who are also on the app. The head of Calvary Christian says they're trying to figure out how a false alert went out.
"Was that human error, glitch in the system? We're trying to figure out what led to that false alarm," said Jason Rachels, of Calvary Christian.
Nate McVicker said there was no glitch in the system. He said the company's files show an alert went out just before 2:30 near the school's library.
"The technology worked 100 percent as it was designed to do, as you guys are covering the story," McVicker said. "The alert went out and it alerted all those police officers. It alerted the staff and they were able to easily mitigate the situation."
McVicker said he plans to help the school figure out how this alert mistakenly went out.
Rachels said staff at the school handled the situation well.
"I think parents can be very encouraged by the response time, how it was handled and know that we're going to take every situation seriously," Rachels said.
Several students said they felt very safe and reassured by the teachers and staff on campus.
"I felt very safe. Our teachers were able to make us feel very safe and comfortable," said Gabriella Velasquez.
Meanwhile some parents said use this experience to push for more security on campus.
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