It was the elderly gentleman's son and daughter-in-law who alerted the emergency services in the village of Leffinge, outside the seaside resort of Middelkerke. The son and daughter-in-law also descended into the well in an attempt to rescue their father, but they too became unwell as a result of the poisonous fumes that had gathered at the bottom. They too fell into the well, but could be rescued by the emergency services.
One of the rescue workers too inhaled the toxic fumes and needed treatment in hospital.
Toxic fumes collect at the bottom of wells when rotting materials like leaves gather at the bottom.