In early 1976, the bodies of two tourists were found burnt on the side of a road north of Bangkok, Thailand. They had smoke in their lungs, meaning they had still been breathing when they were set on fire. They were initially reported as missing Australian backpackers, but after Dutch diplomat Herman Knippenberg received a letter about two Dutch tourists who had uncharacteristically stopped communicating with their families in February 1976, he began to investigate further. He eventually matched the dental records of the missing Dutch couple to the burned bodies.