Return of income filed by assessee was accompanied with computation of income, trading and profit and loss account as well as balance sheet along with fixed assets account and capital account. At time of issue of notice, Assessing Officer was merely having information about cash deposit of Rs.12,97,900/- in his savings bank account. The  Assessing Officer had issued notice under section 143(2)/142(1) but also issued questionnaire, that too along with notices which was served on spot on date of filing of return to counsel of assessee. Tribunal held that the Assessing Officer did not have any information about what kind of business assessee was doing, whether bank account in which alleged cash was deposited appeared in balance sheet, whether level of income shown by assessee justified amount of cash deposited, etc. it could be said that, Assessing Officer did not thought it ‘necessary’ but issued notice in a mechanical manner. Tribunal also held that before issue of notice, Assessing Officer had to examine return filed by assessee but same was not done and in such a situation, assessment order passed under section 143(3) was to be quashed. (AY. 2010-11)