It all started when a video was posted on Snapchat showing the two students inside Platt High School in Meriden, north of New Haven.
One of the students appears to be flashing the prop gun.
Officers found the students in the school's auditorium and detained them.
"I was just sitting in my class, we locked the doors, pulled the shade down, but I didn't really freak out, but then at the same time I did freak out because somebody is in there with a gun and I could have been next to him," a student said.
"At first, they were trying to have us go to our classes and I was like, I want to leave, I don't want to be here," another student said.
The students have been charged with breach of peace.
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