The prosecution questioned former Industry Minister Paik Un-gyu on Monday as part of its probe into the controversial closure of South Korea's second-oldest nuclear reactor.

The Daejeon District Prosecutors Office grilled Paik over allegations that he abused his authority in the process of assessing the economic viability of the Wolsong-1 nuclear reactor ahead of its closure.

In October 2020, state auditors said the economic viability of the nuclear reactor was unreasonably undervalued in determining the facility's early closure.

The Board of Audit and Inspection questioned the general credibility of the process in calculating economic numbers of the reactor, saying that Paik is one of the leading figures in the mishandling of the assessment.

The former minister is also suspected of being involved in the deletion of documents related to the reactor closure by three industry ministry officials.

The three officials were indicted over allegations that they destroyed 530 materials and files about the government's decision to terminate the operation of Wolsong-1, right before the BAI ordered the submission of the documents late last year.

The closure of Wolsong-1 has remained a hot-button issue in domestic politics since President Moon Jae-in decided in 2017 to decommission the reactor earlier than scheduled in line with his energy policy. (Yonhap)