City of Poughkeepsie Fire Chief Mark Johnson said a "very pungent" odor of gas was evident when firefighters arrived on scene and suggested evacuating students as a precaution.
"Until air quality and the explosive limits could be checked by Central Hudson it was best to evacuate the students," Johnson said.
Students were evacuated to the nearby athletic field where lunch was provided as they waited for Central Hudson Gas & Electric to respond to fix the leak.
Parents were notified via email and some students were picked up at the athletic field.
"The heavy smell of the gas did its job and alerted school officials to the problem," Johnson added.
The small leak on the boiler has been repaired and school is currently in session. School officials said all after-school activities will take place, school officials said.
Parents with concerns or questions should call the school at 845-451-4891.
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