Cheshire Academy was on lockdown and a dorm on campus evacuated on Tuesday.
The school has since been cleared and students are back in the Von der Porten Hall dormitory.
Police were investigating a report of potentially hazardous materials on the grounds of Cheshire Academy. A student was reportedly being "suspicious" with potentially hazardous material, Cheshire police said.
Cheshire Police along with state police searched the grounds and seized a liquid believed to be gasoline in a wooded area off the main portion of the campus.
According to the school's website, all students safely evacuated from Von der Porten Hall. Parents of day students were able to come pick up their children via the Route 10 entrance.
There is no immediate threat staff or students, according to Cheshire police.
Photo Credit: NBC Connecticut
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