A state agency affiliated with the Korea Customs Service (KCS) has come under probe from the prime minister's office over its alleged construction of a "ghost" building in the central administrative city of Sejong, informed officials said Thursday.

The Office for Government Policy Coordination sent its inspectors to the Customs Valuation and Classification Institute (CVNCI), a KCS affiliate headquartered in Daejeon, central South Korea, to look into its controversial construction of a new headquarters building in Sejong and its employees' alleged property speculation, they said.

The controversy erupted after it was belatedly disclosed that the CVNCI, which is in charge of customs assessment on imported and exported goods, built the Sejong building after obtaining a 17.1 billion won ($15.1 million) budget from the Ministry of Economy and Finance in 2015, though it was not included in the list of government agencies eligible for relocation to the central administrative city.

In 2018, the Ministry of the Interior and Safety put the brakes on the new CVNCI building but to no avail. The new CVNCI building was completed in Sejong in May last year and has since remained empty, with some critics dubbing it "a ghost building."

Despite the unsanctioned relocation, as many as 49 out of CVNCI's 82 employees purchased coveted apartments in Sejong through a special allotment for civil servants serving in the administrative city, triggering another controversy of unlawful property speculation.

According to the informed sources, inspectors from the Office for Government Policy Coordination also visited KCS and other government offices to gather data related to the empty Sejong building.

Earlier, Prime Minister Kim Boo-kyum instructed government officials to conduct a strict investigation into the CVNCI case and consider various countermeasures, including referral of those responsible to the investigation authorities and cancellation of the sale of Sejong apartments to CVNCI employees.

The CVNCI case is expected to be handled seriously by the government, as it has come on the heels of illicit property speculation scandals involving employees of state-run Korea Land and Housing Corp. and other public officials accused of using insider information for lucrative land and house purchases. (Yonhap)