By Lee Hyo-sik Staff Reporter A fire broke out at Sungnyemun _ more commonly known as Namdaemun, meaning South Gate in Korean _ a historic structure from the Joseon Kingdom located in the center of Seoul, Sunday night, causing a major problem for firefighters. The fire occurred around 8:50 p.m., police said. About 30 fire trucks along with 90 firefighters rushed to the scene to bring the blaze under control. There were no reports of any casualties and the cause of the fire has yet to be determined, they said. According to firefighters, Namdaemun did not seem to sustain major damage other than minor burning to the area underneath the roof. Police suspect someone deliberately started the fire as a taxi driver, identified only by his surname Lee, said he saw a man in his 50s go up the stairs of the gate with a shopping bag, while he was waiting to pick up a customer in the nearby area. Lee said he then saw a spark like a firework and reported it to police, adding the man came down the stairs afterwards. The taxi driver said he drove around looking for the man but could not find him. About 40 police officers were dispatched to the scene and questioned eyewitnesses to identify the cause of the blaze. Also, some roads were blocked to traffic as firefighters put out the fire. Namdaemun, the oldest wooden structure in Seoul, was originally built in 1398 and then renovated in 1962, following its destruction during the Korean War. It was given the status of National Treasure No. 1. leehs@koreatimes.co.kr