A black box recording from a passing driver captures the moment a bridge structure under construction collapsed in Anseong, Gyeonggi Province, Tuesday. Yonhap

Four workers were killed and six others were injured after bridge structures collapsed during construction in Anseong, Gyeonggi Province, at 9:49 a.m., Tuesday.

According to fire authorities, five 50-meter-long steel supports for the bridge fell to the ground from the piers for the construction of the Seoul-Sejong Expressway.

Of the 10 workers on the upper parts of the bridge, four were killed. Seven of them were Koreans and three were Chinese nationals.

The injured workers were sent to nearby hospitals for treatment. Five of them are in serious condition, according to the hospitals.

The bridge's height varies by section, but the maximum height is 52 meters, and the distance between the piers was 210 meters.

Fire authorities conducted rescue operations at the scene, deploying 172 personnel from Gyeonggi, South and North Chungcheong provinces.

Acting President Choi Sang-mok urgently directed the Ministry of the Interior and Safety, the Ministry of Land, Infrastructure and Transport, the National Fire Agency, the National Police Agency and the South Chungcheong Province government to deploy all available personnel and equipment for rescue efforts and search operations for missing individuals.

The search was concluded after the final missing person was found dead at 2:21 p.m.

Seen is an aerial view of the bridge that collapsed during construction in Anseong, Gyeonggi Province, Tuesday. Yonhap

The Seoul-Sejong Expressway, which runs 134 kilometers in total, is divided into two parts: the 72-kilometer section from Anseong to Guri, Gyeonggi Province, and the 62-kilometer section between Sejong and Anseong.

The first section was opened on Jan. 1 and the second section was scheduled to open by the end of 2026.

The site of the accident is included in the Sejong-Anseong section.

"We deployed all employees related to the construction to the scene and are focusing on dealing with the accident," said an official from Hyundai Engineering, which is in charge of construction at the accident site. "We are grasping the details of the situation, such as how many field employees are employed by subcontractors."

Meanwhile, the Ministry of Employment and Labor launched an investigation to check for possible violations of the Occupational Safety and Health Act and the Serious Accidents Punishment Act in connection with the accident.

Immediately after the accident, the labor ministry dispatched an industrial accident prevention and supervision officer to order the suspension of further construction work there for the time being.

A violation of the Serious Accidents Punishment Act could put the CEO of a company behind bars if a serious worksite accident involving death occurs due to the company's insufficient safety precautions.