Residents near the JBS Swift meat-packing plant in Butchertown are no longer being advised to stay indoors because of an anhydrous ammonia leak inside the plant. Officials gave the ‘all clear’ around 2:20pm. The leak was first reported shortly before 11:30. Warning sirens were sounded about an hour later, after emergency workers assessed the scene. No chemicals were detected outside of the Swift building, and a MetroSafe official says the warning to stay indoors was precautionary. Swift employees were evacuated but have moved back into the plant. One person was taken to the hospital on a non-emergency call after reporting nausea.MetroSafe workers could not say whether any animals have been moved from the plant.