On April 16, firefighters and other officials continue the search operation for the missing persons at the site of the collapse of the double-track ShinAnsan Line Section 5-2 in Iljik-dong, Gwangmyeong City. /Courtesy of News1

The construction accident investigation committee for the Gwangmyeong Shinansan Line announced on the 16th that it will extend the investigation period for the collapse accident at the construction site of section 5-2, which occurred on April 11, by three months. Accordingly, the investigation period is extended to September 14.

Starting with the initial meeting on April 17, the committee has been conducting efforts to identify the cause of the accident through three site investigations, six committee meetings, two hearings with related parties, analysis of 3D video footage, review of design documents, and discussions on collapse scenarios by specialty.

The committee judged that additional structural analysis of the structural calculations and drawings, geological and ground investigations of the accident section, and structural interpretations during different stages of tunnel construction were additionally necessary, so it decided to extend the investigation period by three months. During the extension period, additional analyses will be carried out through specialized companies.

Commissioner Son Murak said, "We are keeping all possibilities open regarding the cause of the accident and are thoroughly reviewing even minor details from multiple angles," adding, "We will comprehensively review the results of the accident investigation so far as well as the additional analysis results from specialized companies to objectively identify the cause of the accident and establish measures to prevent recurrence as soon as possible."