Rescue workers have temporarily suspended the search for two missing people in the debris of a collapsed library construction site in Gwangju.

Gwangju's fire department said Friday that authorities need time to stabilize the mass of tangled steel bars, rods and wreckage that are hampering rescue operations and to ensure the safety of emergency personnel.

Authorities plan to resume their search for the missing workers around 6 p.m.

Searchers are using thermal imaging cameras and rescue dogs during their operations. Heavy equipment, including large cranes, has also been deployed to stabilize the collapsed structure and prevent further collapse.

Progress has been slow due to the mass of debris and concrete that was poured at the construction site on Thursday, which is beginning to harden in the cold weather.

The collapse occurred around 2 p.m. Thursday. Two workers have been confirmed dead, and two remain unaccounted for.