Delhi Police on Wednesday filed a case on the suicide of a farmer from Rajasthan at an Aam Aadmi Party (AAP) rally here against the controversial land ordinance.Police registered the case under charges of causing abetment of suicide, death by negligence and obstructing public servant in discharge of public functions."We have registered a case. The case has been transferred to our crime branch to proceed further inquiry," said a police officer.Gajendra Singh hanged himself from a tree in central Delhi's Jantar Mantar. He was rushed to Ram Manohar Lohia Hospital where doctors declared him dead.AAP leaders earlier blamed Delhi Police, saying police did not even respond to their appeals to bring the man down from the tree. IANS