Income-Tax authorities are probing the sources of income of several prominent politicians who are members of an elite housing society in a posh locality of the capital. The I-Tdepartment has issued notices to the Nav Vihar Sansad Society, whose members are all former and present MPs, in west Nizamuddin, asking its management to furnish details on the mode of payments by its members, sources said yesterday. The society with over 400 members is constructing the VIP flats on a five-acre prime land, the sources said adding that the matter came to light during the interrogation of Prakash Chandra Yadav, son of former fertilisers minister Ram Lakhan Singh Yadav, two months back in connection with the multi-crore urea scam. The sources, however, declined to disclose the names of politicians who are members of the society.