NEW DELHI: The CBI is conducting an internal enquiry to ascertain how an internal draft report pertaining to the Aircel-Maxis probe reached former FM P Chidambaram 's residence.According to sources, some unsigned pages of the draft copy of a status report meant to be filed in the Supreme Court , prepared by CBI investigators in 2013, was recovered by Enforcement Directorate sleuths last month from the Jor Bagh residence of Chidambaram's family.CBI spokesperson Abhishek Dayal said, "We are looking into the matter".TOI texted P Chidambaram for his comments, to which he replied, "Let the agency ask me".The ED had conducted a raid at several premises in Delhi and Chennai on January 13 in its probe against Chidambaram's son Karti. The Congress leader had termed the ED raids against his son "a comedy of errors" and claimed the officers were left "embarrassed" and "apologetic" as they could not find anything at his Jor Bagh house. The ED case pertains to a Foreign Investment Promotion Board approval granted in 2006 by Chidambaram when he was FM.