A 35-year-old woman was killed and 26 people injured, one seriously, following an ammonia leak at a yeast-processing plant on the outskirts of Kozani, in northern Greece, yesterday afternoon. The source and cause of the toxic gas leak at the factory had not been determined by late yesterday, though initial reports indicated that it had come from a high-pressure safety valve. The exact cause of death of the 35-year-old employee had not been confirmed by a coroner yesterday, though an electrician, who suffered severe burns, had been regulating refrigerator temperatures at the time of the leak, sources said. Another 25 factory workers were in the hospital with burns, breathing problems and eye irritation. Kozani Prefect Giorgos Dakis said an investigative committee would be set up to look into the cause of the leak.