A fire at a plant of S-Oil Corp., a major refiner, was extinguished Sunday, about three hours after it started, according to firefighters.

No casualties were reported as the fire erupted at 4:47 a.m., with photos showing dense flames rising from the plant.

An official with the fire authorities in Ulsan said firefighters were “incinerating remaining dangerous substances in a pipe after blocking the production line valve.”

The S-Oil plant is located in Ulsan, some 300 kilometers southeast of Seoul.

Source: Yonhap News Agency