Television footage showed extensive damage to the factory, with part of the building destroyed, effectively splitting the structure in two. Thick smoke could also be seen billowing from the fire.
Violanta said it was “deeply saddened” by the fire.
“Today a serious incident occurred at our factory premises, during the night shift, for a currently unknown reason,” Violanta said in a statement.
“We are fully cooperating with the relevant authorities and providing all available assistance.”
Health minister Adonis Georgiadis earlier told the Skai news agency that six workers and a firefighter had been taken to hospital, adding that they were “in good health, mainly suffering from respiratory problems”.
The fire service said more than 50 firefighters and 16 fire trucks had been sent to tackle the blaze.
Prime Minister Kyriakos Mitsotakis referred to the fire during opening remarks at a cabinet meeting on Monday.
“Our thoughts are with the families of the victims,” he said, adding that the fire service was already investigating the circumstances of the incident” so that “responsibilities can be established”.
