A refinery run by the Toho Zinc Co., Ltd., which was established in 1937, discharged cadmium into the air and the river. In the following years, the impact was apparent and residents soon led an organized protest, complained about the destruction of their silkworm production as well as fish and agricultural production downstream. In the 1960s, TEPCO, which wanted to increase power supply to the refinery, logged communal forests without permission, leading to another level of environmental protest. In 1969, 309 residents with the help of 239 lawyers filed a claim in court asking for injunction to the refinery expansion, which was granted in the following month. This was the first injunction granted against the mineral refinery. In 1970, rice in An-naka was found to be contaminated with cadmium. A scientific study described the situation as follows: "In Annaka City, Gunma Prefecture, where the largest zinc refinery of Japan is located, about 200 samples of agricultural products, soil, silkworms, and excrement of the farmers were collected and analyzed to verify the environmental pollution by the refinery. As a result, it was found that the content of cadmium and other metals in mulberry leaves for silkworms and in wheat flour shows a remarkable relation to the distance from the refinery chimney, and further, that the content of cadmium and other metals is remarkably higher in leaf vegetables such as cabbages compared with root vegetables, fruit vegetables, or cereals. Thus, it was made clear that the hilly regions higher than the refinery, are polluted only by metal-containing air, while the lower rice field regions are affected by waste water, as well as, polluted air". (Kobayashi, J).