Twelve people were injured on Thursday afternoon following an explosion at the Repsol plant in La Pobla de Mafumet, Tarragona.
The blast occurred at 17:15 at the Planta de Olefinas, part of the Repsol Industrial Complex. The injured were treated in the first instance by medics at the site. One of the wounded was later transferred to the Hospital Joan XXIII in Tarragona.
Investigators are trying to ascertain the cause of the blast which occurred in a network of drainage pipes.