KOLKATA, June 25, 2016 (Xinhua) -- Indian school children participate in "A Walk for Anti-Drug Movement" ahead of the International Day against Drug Abuse and Illicit Trafficking in Kolkata, capital of eastern Indian state West Bengal, June, 25, 2016. The International Day against Drug Abuse and Illicit Trafficking is observed on June 26 every year. (Xinhua/Tumpa Mondal)