A tank at an oil refinery in the southeastern city of Gumi exploded Thursday, with no injuries reported, police and fire officials said. The 200,000-liter tank containing 4,000 liters of bunker C fuel oil at the Kyung Buk Kwang Yu Co. refinery located in Gumi, some 200 kilometers southeast of Seoul, exploded around 8:21 a.m., they said. A small stream runs nearby the refinery, but no oil has been found to have leaked, they added. Over 190 firefighters with the use of 20 fire engines were able to extinguish the blaze in about 30 minutes, they said. The explosion comes just two days after a chlorine gas leak at another chemical factory in Gumi, causing nearly 200 people to receive medical attention.