By Bill Shields

WALPOLE (CBS) – Shots rang out and as smoke filled the hallway, teachers and staff barricaded themselves in the classrooms.

Teachers at Norfolk Agricultural School came face-to-face with a pretend active shooter, and were given just seconds to react.

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“The sound of the gun was really scary,” said Cathy Lemire, a staff member at the school. “It just made you think that something bad was really going to happen.”

But this training wasn’t for the Walpole Police officers, who were shooting blanks.

A teacher stacks desks during an active shooter drill at Norfolk Agricultural High School (WBZ-TV)

A teacher stacks desks during an active shooter drill at Norfolk Agricultural High School (WBZ-TV)

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It was for the teachers and staff.

“They’re technically going to be the first responders,” said Walpole Police Chief John Carmichael. “The staff is already here on campus.”

As the shooter tried to get into the classrooms, teachers barricaded and locked the doors. Then, the smoke alarms went off, adding to the confusion.

The teachers were quick to learn.

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“We just need to make sure that we have done everything we can to make sure students are safe, teachers are safe and the community is safe,” Superintendent Suzanne Green said.