Black smoke is seen from a chemical factory in the Daesan Petrochemical Complex in Seosan, South Chungcheong Province, Feb. 25. Yonhap

The operations of LG Chem and Lotte Chemical plants at an industrial complex in the central city of Seosan were halted Tuesday due to a power outage, company officials said.

The incident occurred around 9:30 a.m. at the two plants located in the Daesan Petrochemical Complex, about 100 kilometers south of Seoul, they said.

Amid the suspension of plant operations, the two companies were burning raw materials used in the production process, giving rise to black smoke pouring out of the factory chimneys.

The officials said that even if power supply is restored, it will take a long time for factory operations to return to normal.

The companies are expected to suffer losses amounting to billions of won due to the incident.

Meanwhile, KEPCO, the state power utility, said there is no problem with its power lines in the region, speculating there may be a problem with the clients' facilities. (Yonhap)