Since the 60s there are conflicts between the Cinta Larga Indians and groups of artisan miners interested in exploiting diamond deposits in their traditional lands, an area of more than 2.6 million hectares designated by the Brazilian State as TI Roosevelt. According to studies conducted by the Departamento Nacional de Producao Mineral - DNPM, this deposits has the capacity to produce at least one million carats of diamonds. Although the Brazilian Constitution considers mineral exploitation on indigenous lands as illegal, there are bills seeking to revise it and regulate mining in this lands. The Agencia Brasileira de Inteligencia - ABIN estimates that at least 10% of the full potential of the deposit has already been removed illegally over the last fifty years.
Since 1969, the Brazilian State, through the FUNAI, started operating in the region. However, his performance was held in order to calm down the Indians and ensure continuity of mining. At that time, an Indian reservation was created to ensure the maintenance of the territory Cinta Larga. The boundaries of Indian lands have been revised several times, always reducing its total length.
Since then, the Indians Cinta Larga have being murdered by miners and occasionally also kill some of them. Out of the 5000 Cinta Larga people inhabiting the region in 1960, little more than 2000 still survive. Since 2002, the Cinta Larga intensified actions to pull miners out of their lands. In order to survive in an ever smaller and more cleared territory, they began to explore the diamonds themselves and sell them to international smugglers.
In 2003, the Ministerio Publico Federal - MPF reported that members of the Centro Mineiro de Conservacao da Natureza would be acting as representatives of the Companhia de Mineracao do Estado de Rondonia to negotiate diamond mining with the Indians. According to prosecutors, the then Governor of the State of Rondonia, Ivo Cassol, would be personally involved. In the following year, a Federal Police operation arrested at least 15 people for illegal exploitation of diamonds in Cinta Larga lands, many of whom State officials. Several Cinta Larga were murdered that year. As reprisal, Indians killed 29 miners in a joint action with other ethnic groups.
Since 2010, the indigenous leaders decided to suspend the mining on their lands, and rely on the support of the Federal Police to ensure that miners are out of it. However, Indians do not have their basic needs met. Occasionally, the FUNAI donates food baskets but many social projects intended to compensate them and ensure the development of their territory remain unimplemented. Therefore, illegal diamond mining is spreading quite fast. The Brazilian State has undertaken actions to curb this practice, but still do not guarantee to Indians sufficient alternatives for their livelihood.