Waterloo, IL (KSDK) - Gibault High School students were sent home from class Tuesday afternoon after a gas leak prompted an evacuation.

School employees smelled gas and contacted city workers to inspect. They took a measurement and the readings were high, so 240 students were evacuated to the front lawn of the school around 8:00 a.m.

The leak was reduced to an "acceptable" level shortly after 11 a.m.  Students were intially let back into the building, but dismissed for the day shortly afterward.

KSDK