GOYANG, Gyeonggi Province -- Firefighters have completely put out the massive blaze that engulfed an oil storage tank northwest of Seoul, some 17 hours after the initial explosion, authorities said Monday.

The fire services of Gyeonggi Province said the extinguishing work was completed at 3:58 a.m. on Monday and that no risk of additional fires was present.

They said they will conduct a joint probe with related authorities to determine the exact cause of the fire.

The fire broke out at a gasoline storage tank -- owned by Daehan Oil Pipeline Corp. -- in Goyang, a city just northwest of Seoul, about 11 a.m. on Sunday, after an explosion believed to have been caused by oil gas.

The operator of South Korea's oil pipelines offered a public apology for the explosion and fire and vowed to ensure that a similar accident does not recur.

Daehan Oil Pipeline also said it will make sure that a stable supply of energy is not affected in anyway.

Daehan, a former state-run company that was privatized in 2001, built and operates 1,081 kilometers of pipeline network across the country. Currently, SK Innovation Co., South Korea's largest refiner by sales, owns a 41 percent stake in the oil pipeline company.

There were no casualties as no employees were working at the time, and the storage tanks are in a remote location away from residential towns. The fire was also contained before it spread to other tanks.

But the roaring blaze created a thick belt of black smoke running through the sky and sent up toxic fumes visible from the eastern district of Jamsil, some 25 km away from Goyang.

The authorities mobilized 224 units of equipment, including fire helicopters, and more than 680 firefighters were sent to the scene. Authorities sent alarm messages to residents nearby advising that they stay at home and keep all doors shut.

The fire in the 8.5-meter-high, 28.4-meter-radius tank burned 2.66 million liters of gasoline, and some 4.4 million liters remain in the tank, enough to fill 250 tank trucks, the authorities said. (Yonhap)