A toxic chemical leaked at a factory in the southeastern city Gumi on Tuesday, causing seven workers to be taken to the hospital.

The leak reportedly occurred at around 1:47 a.m. at the plant of KEC, a semiconductor manufacturer, in the city in North Gyeongsang Province.

The workers were reportedly not in critical condition. 

The toxic chemical, trichlorosilane, is a colorless liquid that smells of hydrogen chloride and can cause breathing difficulties, headaches and dizziness if inhaled.

Fire authorities and municipal officials went to the scene to prevent further leakage and had the situation under control by 3:22 a.m. An investigation is under way to determine the scope and cause of the leak.