As a mob stormed into the Presidency College in Kolkata and used spears and other weapons to attack students and property, a local leader from Mamata Banerjee's Trinamool Congress stood at the gate along with three activists of the party's student wing. The footage, broadcast on a Kolkata channel today, undermines the Trinamool's denials of any links to the 30-minute rampage at one of Bengal's most prestigious education institutions.