Enrico Amati, 47, of Sinalunga, near Siena in northern Italy, was burned over 90 percent of his body and died a day after the explosion, the Italian news agency ANSA reported.
The Ilsap Biopro facility in Lamezia Terme in Calabria exploded Thursday, officials said.
Two men who died in the blast Thursday were identified Friday as Daniele Gasbarrone, from Latina near Rome, and Alessandro Panella, from Velletri in Calabria. Both were 32.
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