Two workers are believed to be trapped after a collapse occurred at a construction site for the Sinansan subway line in Gwangmyeong, Gyeonggi Province.

According to the Gwangmyeong Police Station on Friday, the collapse occurred around 3:17 p.m. near Yangji Intersection.

While no casualties have been officially reported, fire authorities believe that two people are currently trapped.

Earlier, around 12:30 a.m., authorities received a report that multiple central pillars supporting the underground tunnel at the construction site had cracks. 

The surrounding roads were completely closed to traffic in response.

Parts of a nearby road and facilities aboveground were also damaged.

The city of Gwangmyeong sent out a disaster alert message, warning of the risk of further collapse in the direction of Yangji Intersection. They urged drivers to use alternate routes and advised nearby residents to evacuate.