The Enforcement Directorate (ED) on Wednesday conducted searches in four states as part of an investigation linked to an alleged bogus Corporate Social Responsibility (CSR) donation racket, officials said.Sources said a total of eight locations in Maharashtra, West Bengal, Gujarat and Delhi-NCR were covered as part of the action. The premises belonged to market operators, trustees and middlemen after it was prima facie found that a bogus CSR racket was operating, which allegedly ran into hundreds of crores of rupees, they said.