A local resident notified the fire department and government authorities after observing suspicious smoke escaping from a 2,000-m² hangar housing some 8,000 tonnes of bone meal (max. storage height: 10 m). The suspicious parts were covered; however, fumes were once again noticed several hours later, prompting an evaluation. Fire-fighters wearing self-breathing apparatuses recorded the temperature (118°C in spots). Ammonia concentrations of 80 ppm were measured. Self-heating of the meal was facilitated by having sprayed an insect repellent solution a few days prior. The depot remained under close watch for several days and measures were adopted to stimulate cooling of the meal (heat probes, spreading into thin layers, a cover to limit air intake, etc.) and its removal to installations authorized for such disposal. This same kind of event would be observed at another depot just a few kilometres away.