Mitsui Chemicals on Monday apologized for a gas leakage incident at a plant at its Omuta Works site in Omuta, Fukuoka Prefecture.

"We deeply apologize for the significant trouble caused to many people," the company said. It is gathering information on the possible impact on product shipments.

According to Mitsui Chemicals, the leak occurred at a polyurethane material plant, where a chlorine gas detector was activated around 5:40 p.m. Sunday, triggering an emergency shutdown of the plant.

The leakage stopped at 7:05 p.m. the same day, but 42 individuals were taken to hospital.