At least 45 people are now known to have died in a fire at a rubber shoe factory in a suburb of the Philippine capital Manila, local officials say.
With more than 26 people still unaccounted for, the death toll is expected to rise.
Firefighters battling the blaze on Wednesday found no survivors after bringing it under control.
Most of the victims are thought to have suffocated in thick black smoke from burning rubber and chemicals.
The Mayor of the Valenzuela suburb Rex Gatchalian said the government was "still praying and hoping that the 26, some of them, must have gotten out earlier in the morning and had gone to relatives" without telling officials they were safe.
Some of the bodies were still inside the building on Thursday morning.
The fire was reportedly started when sparks from welding work ignited flammable chemicals near the building's entrance.
The fire spread quickly and a few people escaped, but many more were trapped on the second floor of the building.
Some of those trapped texted family members asking for help, local media reported.
The factory is operated by Kentex Manufacturing, and produces rubber flip flops and sandals.
The fire took more than five hours to bring under control, and recovery of bodies has been suspended while engineers make the building safe.
The Philippines has lax safety standards and large fires are relatively common, particularly in slum areas.