A worker who was trapped after a collapse at a construction site for the Sinansan subway line in Gwangmyeong, Gyeonggi Province has been rescued.

Fire authorities said the man, in his 20s, was pulled out at 4:32 a.m. on Saturday, 13 hours after the collapse. 

In a press briefing, an official from the Gwangmyeong fire agency said the worker was conscious and was being transferred to Ajou University Hospital. 

However, a second missing worker remains unaccounted for, and has not yet been found.

The collapse occurred at around 3:13 p.m. on Friday, while workers were conducting inspection and reinforcement work. The response came after a report was filed just after midnight about cracks in multiple central pillars supporting the underground tunnel.

Of 18 workers at the site, two went missing in the collapse. 

The city of Gwangmyeong issued a disaster alert and advised nearby residents to evacuate. But the alert was lifted at 12:10 a.m. Saturday after safety inspections.