According to the Basque Department of Safety, the accident at work occurred at 04:30 a.m. on Monday through Tuesday. In the paper company Smurfit in Iurreta (Bizkaia), when the factory was being cleaned, workers are believed to have inhaled toxic substances.

At first, two workers have been transferred to the hospital in Galdakao for care. The third has been initially treated in a medicalized ambulance, but has also been transferred to the hospital to be treated for her injuries.