A Florida middle school announced a lockdown and Thursday, and police officers burst into classrooms with guns drawn. At least one of the guns was an unloaded AR-15, an automatic weapon.

The episode was part of an unannounced "active shooter" drill, and both teachers and students were unaware of what was taking place.

"All of sudden there was a gun barrel," Jewett Middle Academy eighth-grader Xavier Tate told "Fox & Friends."

"We didn't know it was a drill. We thought it was a gunman (coming) right through the door," he said. "It was very scary."

Some students were so terrified that they texted their parents during the lockdown.

"We actually thought that someone was going to come in there and kill us," seventh-grader Lauren Marionneaux told MyFox Tampa Bay. Marionneaux texted her mother, Stacy Ray, who was shaken.

"I'm panicking because I'm thinking that it's a legitimate shooter coming, that something bad is happening at the school," Ray said. One of her other children also texted her saying: "I thought he was going to shoot me."

Another Winter Haven mother received a phone call about the "active shooter" situation.

"When a friend called and told us there was a shooter at the school my husband...raced to get to the school," she recounted. "He was so afraid. All he could see was Columbine."

A Polk County Schools spokesman said that it is common practice for an active shooter drill to be announced without warning teachers, students, or parents, but also expressed regret for "any concern that parents and students might have experienced."

Winter Haven Police Chief Charlie Bird said that future drills will include uniformed officers without guns, but defended active shooter drills in general.

"It really is to protect the children," he insisted.