Concerned about security at their school and the suspension of a history teacher who questioned that security last week, dozens of Cherry Hill East High School students participated in a brief sit-in demonstration Monday.

Last week, teacher Timothy Locke was suspended after discussing his concerns about security during one of his classes, the teacher says.

“The bottom line is that I was very concerned about the security at my school,” Locke told Philly.com. “I was adamantly concerned with the welfare of my students.”

Locke told New Jersey 101.5 he’s been advised by his attorney not to discuss the situation — but still said his comments were made out of abundant love for students, and he would make them again.

Video posted to YouTube shows students crowding their halls amid commotion. CBS Philadelphia news reported seeing other video with students shouting "Free Locke!"

Shortly after Monday's protest began, students were advised to instead meet with Principal, Dennis Perry immediately in the auditorium — or face suspension, according to teens at the school.

“People were asking questions like 'What happened to the teacher?' 'Why was he suspended?' but Dr. Perry told us he couldn’t give us any information about what happened,” 16-year-old Rachel Wimmer, one of the students who participated in the demonstration, told New Jersey 101.5.

“People were voicing concerns about security at our school — that’s why the history teacher was suspended. He spoke about the lack of security at our school, and Dr. Perry didn’t really know how to respond to it. He didn’t really have an answer for how we can better the security at our school," Rachel Wimmer said.

In the video seen on YouTube, students ask why Perry won't address the suspension. He told students he could not discuss any specific information about a teacher.

One student on the video says Perry had told students to email him about any concerns — but that didn't lead anywhere. "Now we do something disruptive, and it led to this," the student says.

"If that didn't work before, tell me how it's going to work now," the student says to applause.

Another student tells Perry she's upset the school never had a moment of silence for Parkland, and asks why the only measure she's heard being discussed — nationally or locally — is "fighting guns with guns."

"That's the kind of conversation (that should be had)," Perry tells her.

Rachel Wimmer told New Jersey 101.5 the problem is “you can basically just walk in (and) nobody really checks you. There’s really no security at the front doors.”

Rachel Wimmer said after the recent school shooting rampage in Florida, “it makes us kind of scared that if someone were to walk in, or were to try and harm anybody in the school there wouldn’t be any protection, anything can happen at any time.”

She said the school has two security guards, but they only carry mace and a baton.

“We’re all concerned about our safety, especially after the Parkland shooting. We all want to do something but our administrators don’t really seem to have a clear answer on what we can do," she said.

Melanie Wimmer, Rachel Wimmer's mother, said she recently went to the school and found no security.

“When I got there, a teacher was holding the door open for students. I said I had an appointment with guidance and I walked right in," she said.

She said if someone is not holding the door open, “you push a buzzer, she asks who you are and she buzzes you in.”

Melanie Wimmer said at that point, you sign in, “you’re given a pass, and that’s it.”

“There’s no security at the door, there’s nobody checking bags, there’s literally nothing," she said. "I could have walked the entire school if I wanted to and nobody would have stopped me.”

Melanie Wimmer said she’s worried “because it seems like these incidences are happening more often.”

She said when it comes to security, “there’s no notification to the students, there’s no notification to the parents.”

Students are planning another protest at the school tomorrow morning.

Multiple calls to the school Principal Perry a spokesperson for Cherry Hill East high school seeking comment have not been answered. New Jersey 101.5 reached Locke, but on his attorney's advice, he said only that he'd made his statements out of concern for his students.

Locke told Philly.com that after he made the comments in class, he was put on administrative leave and ordered to undergo physical and psychiatric evaluations.

“All I have ever done for that school is for my students and for their parents,” Locke told the site.

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