ARLINGTON, Texas (CBSDFW.COM) – Two teenagers were arrested for allegedly bringing a loaded handgun to Arlington’s Nichols Junior High Wednesday.

The loaded gun was in a student’s backpack and Arlington Police said it was likely being carried around on Monday and Tuesday as well.

Police said the student who reported the gun on Wednesday, first saw it Monday, but told staff the boy who had it, had threatened her not to say anything.

She didn’t say anything about it until Tuesday evening, when she told her parents about it.  They told her she had to tell the school Wednesday morning. She did.

School staff came in, cleared the classroom, then found the gun a backpack.

“The school district actually froze the classroom,” explained Arlington Police spokesperson Chris Cook. “She was able to describe the student and they pulled all the kids out. Then we did a methodical search, or actually the school district did. They located a firearm and that’s when PD was brought in.”

The girl whose backpack the gun was found in was charged with unlawful possession of a firearm. A boy was also charged with that, as well as for making a terroristic threat.

“You cannot take this stuff lightly,” said Cook. “You always need to report it. We’ll do everything we can to protect your identity but if you know of or have information that someone has a firearm or is planning to do something, we’ve been having this conversation for years. We’ve got to know about it.”

Police do not yet know who owns the gun or why the student had it at school.

AISD told CBS 11, there are metal detectors that are used for random checks or when needed at the school, but they are not out every day. 

Wednesday afternoon, Arlington’s Police Chief Will Johnson tweeted, “This needs to serve as a reminder that we will not allow guns in our schools.  We arrested two teenagers today for bringing a loaded Glock 26 handgun to Nichols Junior High.  We continue to work with our schools to educate kids and parents on this issue.”