A total of 19 people were injured at the Neptune Technologies plant in Sherbrooke, Quebec, news agency QMI reported. Four were airlifted to a burn center in Montreal, The Record of Sherbrooke reported.
The plant manufactures omega-3 oils from krill, tiny oceanic shrimp. Investigators said the fire began in barrels containing flammable acetone, although they were unsure what started it.
A huge plume of dark smoke rose into the air during the fire. While local officials said it posed little risk to those on the ground, the industrial park was evacuated. Dr. Melissa Genereux, working for the local public health authority, said a security perimeter was set up around the plant.
Local residents were also warned to close their windows.