Kolkata, Sept. 9 -- The Enforcement Directorate (ED) on Monday searched more than 20 locations across West Bengal, including Kolkata, in connection with a probe into illegal sand mining from river banks. The raids started simultaneously at around 6am in Kolkata, North 24 Parganas, Jhargram and Midnapore districts. "Multiple ED teams searched several locations in Kolkata and in some districts. Investigation is going on," an ED official said on condition of anonymity. Officials said ED teams searched offices of a private company dealing with sand mining at Salt Lake and residences of the firm's top official. "...There are allegations that sand and riverbed material is extracted beyond the permissible limit and sold illegally using fake challa...