The leak was reported at around 5:30 a.m. Thursday morning. Authorities have evacuated workers from the winery to a nearby police training center.
Authorities are also asking people in the area southwest of the winery to stay indoors, close windows, and turn off heaters or air conditioners.
Click here for a map of the location
One person is being treated for ammonia exposure. There is no word on the patient's condition at this time.
Central Ave. is closed between Polk Ave and Chateau Fresno.
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