The Indian Border Security Force (BSF) on Friday kicked off the 1,200-km Kolkata-Guwahati 'Swarnjayanti Shaurya Pradarsani Yatra' to commemorate 50 years of the Bangladesh Liberation War. The mobile exhibition rally comprising six vehicles was flagged off from the border guarding force's South Bengal Frontier headquarters at Rajarhat on the fringes of Kolkata by BSF (ADG)