Three people were taken to the hospital after an ammonia leak Tuesday evening in North Minneapolis. Crews were called to the Kemps plant, in the 400-block of West Broadway, shortly after 6:30. Captain Paul Baumtrog says the ammonia, which is used as a coolant, began leaking from a piece of equipment inside the plant. Baumtrog says they used water to mitigate the vapors. It's not clear the cause of the leak or how much ammonia leaked. Officials evacuated and blocked off a large area around the plant until they were able to stop the leak. Two firefighters and a plant maintenance worker were transported to North Memorial Medical Center for evaluation after complaining of breathing difficulties.