One of South Korea's most treasured relics was damaged during the heaviest downpours in decades last week, government officials said Tuesday.

Some parts of the roof ridge of Dongdaemun (Great East Gate) chipped off due to the record-breaking rainfall that killed 62 and left thousands homeless in Seoul and its surrounding areas.

Dongdaemun, designated as Treasure No. 1, was the main eastern entrance to the capital city during the Joseon Dynasty (1392-1910).

"A lump of lime-blended clay, which is about 150 centimeters in length and 70cm in width, fell off the upper part of the structure," said Hwang Pyeong-woo, head of the Korea Cultural Heritage Policy Research Institute.

"The ridge plays a key role in solidifying the tiled roof as a whole," Hwang said. "Chances are that the crack would allow rainwater to infiltrate the inside of the structure, which would bring the whole building down if more rain falls."

Seoul's Jongno Ward Office, which is in charge of maintaining the historic landmark, began assessing the damage for restoration earlier in the day after receiving a report from a citizen last week.

"The torrential rains that had lasted well into the weekend delayed the repair work," a district official said. "We are trying to complete application of some repair materials to the cracked part," he added.

The ward office has asked the central government for a 4.5 billion won ($4.28 million) budget to launch an overall maintenance project for the cultural asset next year, according to the officials. 

No maintenance work on the 14th-century wooden structure itself has been completed since 2000, though the ramparts surrounding the main building underwent restoration in 2006.

(Yonhap News)