At least seven people died and three were injured when a Chinese-owned clothing factory in an industrial zone in the Italian town of Prato burned down on Sunday, killing workers trapped in an improvised dormitory built onsite.
Local media said 11 workers had been accommodated in a warren of small cardboard sleeping compartments above a warehouse.
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"This is a disgrace for all of us, because we have to recognize this reality for what it is: the biggest concentration of illegal employment in northern and central Italy," said Enrico Rossi, president of the region of Tuscany.
Footage posted on the website of the local Il Tirreno newspaper showed fire crews battling the flames in a warehouse-like structure while smoke poured out of the building. Ambulances and police vehicles were also on the scene.