Staff of the KBS drama, "The First Night With the Duke" (working title), hammer a nail into the wooden pillar of Mandaeru Pavillion at Byeongsan Seowon in Andong, North Gyeongsang Province, Monday, to hang prop lanterns for filming. Captured from Min Sa-hong's Facebook

The production crew of KBS' upcoming drama, "The First Night With the Duke" (working title), is facing condemnation after driving nails into the Mandaeru Pavilion at Byeongsan Seowon, a UNESCO World Heritage site in Andong, North Gyeongsang Province.

According to architect Min Sa-hong, who witnessed the incident and reported it to authorities, the team hammered five nails into the pavilion's wooden pillars to hang six prop lanterns on Monday, leaving visible damage to the UNESCO World Heritage site.

Constructed in the 17th century, Byeongsan Seowon is an educational institution from the Joseon Kingdom (1392–1910). It is designated as a Historic Site in Korea and is included in two UNESCO World Heritage listings — Historic Villages of Korea: Hahoe and Yangdong and Seowon, Korean Neo-Confucian Academies.

Min shared on Facebook that he spotted several drama props scattered around the site. "Production crews were driving nails into wooden pillars to hang lanterns ... Looking around, I noticed a few lanterns were already hanging from the pillars," he wrote.

According to Andong City, the nail marks were 2 to 3 millimeters thick and about 1 centimeter deep.

Under the Cultural Heritage Protection Act, damaging a designated or registered cultural heritage site can result in a prison sentence of up to five years or a fine of up to 50 million won ($34,000).

Byeongsan Seowon is an educational institution from the Joseon Kingdom (1392-1910). It is designated as a Historic Site in Korea and is included in two UNESCO World Heritage listings — Historic Villages of Korea: Hahoe and Yangdong and Seowon, Korean Neo-Confucian Academies. Courtesy of Korea Tourism Organization

In response, KBS issued an apology on Thursday, acknowledging the harm caused and vowing to aid in the restoration.

"We sincerely apologize for causing concern and are committed to restoring the heritage (site), discussing the best possible methods with authorities," KBS said.

The Gyeongbuk Provincial Police Agency also confirmed the incident on Friday, noting that it received a complaint against KBS for damaging the 453-year-old heritage site.

"It is a serious crime that KBS, a public broadcaster funded by public subscription fees, damaged cultural property for commercial purposes," the complaint stated.

"The First Night With the Duke" is a web novel-based period romance drama starring K-pop stars-turned-actors Seohyun and Ok Taec-yeon. Set for release in the first half of this year, the drama transports an ordinary university student into the world of her favorite romance novel. The adaptation reimagines a European-style romance fantasy into a Korean historical setting, leading the production team to film at Byeongsan Seowon.

This is not the first time Korean broadcasters have faced criticism for damaging cultural heritage sites.

In 2007, staff on KBS' epic drama "Dae Jo Yeong" drove nails into the walls and pillars of Mungyeongsaejae, a historical mountain pass known for its scenic beauty and significance as a key transportation route during the Joseon era. KBS apologized for the issue and promised to prevent similar incidents in the future.

The crew of SBS's "Lovers in Prague" was also accused of damaging the stone walls of Deoksu Palace by attaching paper props with silicone and then removing them with a chisel in 2005.