Operation Cocoon was an operation launched by the Special Task Force of Tamil Nadu Police to capture the forest brigand Veerappan and his associates, who were dominant in Sathyamangalam Forest in the South Indian states of Tamil Nadu, Karnataka and Kerala. The operation was headed by K. Vijay Kumar, and N. K. Senthamarai Kannan.[1][2][3][4] Veerappan was killed on the final day of the operation, 18 October 2004. Three of his associates, Sethukuli Govinda, Chandre Gowda and Sethumani, also died, and four policemen were injured.[3] Veerappan defied the state governments of Karnataka, Tamil Nadu and Kerala and Indian Border security paramilitary forces, and maintained a small army, which at one point numbered hundreds of people. He was wanted for killing approximately 184 people, about half of whom were police officers, including senior police and forest officials. He was also wanted for poaching about 200 elephants and smuggling ivory worth US$2,600,000 (₹16 crore) and about 10,000 tonnes of sandalwood worth approximately US$22,000,000 (₹143 crore).[5] The joint Special Task Force operation to capture Veerappan, was constituted in 1991 by the state governments of Tamil Nadu and Karnataka. It is considered one of the most expensive operations of its kind in Indian history, costing ₹1 billion over the years.[5]