The 500 gallon tank started leaking at around 4 p.m., forcing the Center Moriches Fire Department to evacuate the residents of the nursing home at 6 Frowein Road.
Eight area fire departments and nine ambulances responded to the scene.
14 critical care patients were transported to various local hospitals. The rest were taken to Center Moriches High School.
The leak cannot be stopped, so the fire department is burning off the remaining propane. They are hoping to complete that soon and get the seniors back into their rooms late Tuesday night.
There were no injuries.
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