The school's headmaster put the school in lockdown after a teacher called to report hearing gunshots, the NewsTimes.com reported.
It turned out the noise came from the nearby Danbury Airport, where pyrotechnic shells were fired to scare geese away, the NewsTimes.com said.
The shells are fired when birds are gathering in an area that's dangerous to air traffic, the airport told the NewsTimes.com.
Click here to read the full story at the NewsTimes.com.
Click here to follow Daily Voice Danbury and receive free news updates.