An explosion occurred during the destruction of metal parts that had been polluted by explosive substances. The burning of 342 kg of nitrocellulose, 8.8 kg of cyclonite (cyclo trinitromethyl trinitrosamine) and 11 kg of black powder was prepared on 3 wooden pallets within the combustion zone. A fire protection station was installed 20 m away, with a reinforced concrete wall cover. A few seconds following ignition, a blast occurred injuring two workers. A building was totally dilapidated, while another sustained damage. The use of 350 kg of explosive powder instead of 100 kg was most likely responsible for transforming the combustion reaction into a detonation.