Both were Bulgarian nationals, according to information from local fire brigade and hospital sources.
The first person succumbed on the site, according to the chief of the local Fire Brigade Yorgos Vlontzos. The second person, who had extensive burns, was being monitored in the intensive care unit of a local hospital, a source with the hospital said.
The fire, which was followed by explosions, caused the collapse of the roof and a major part of the factory. It was put under control by dozens of firemen who rushed to the area.
So far, investigators have not found the cause of the accident. According to eye witnesses, the fire broke out when the two men were trying to cut metal parts of the building and sell them.
There might be other people trapped in the factory, according to earlier reports. But it was not confirmed by authorities.