The last of four workers buried under debris in an accident at the Gwangju Metropolitan Library construction site has been confirmed dead.

Fire authorities said the worker was discovered with no vital signs around 11:20 a.m. Saturday, and rescue teams worked for more than an hour before pulling him from the collapsed structure around 12:40 p.m.

The man was taken to a hospital by ambulance and later pronounced dead. 

Officials said he had been carrying out plumbing work in the basement at the time of the accident.

Earlier, fire authorities found the third victim dead at 1:03 a.m. Saturday.

The collapse occurred around 2 p.m. Thursday at the construction site in Chipyeong-dong in the city’s Seo District, as concrete pouring work was taking place on the roof of the building.