MUMBAI: Over the next fortnight, the tax office will ask everyone who deposited more than Rs 10 lakh in their bank accounts after November 8 to spell out the source of money. There are about 1.5 lakh bank accounts in which Rs 10 lakh or above has come in since announcement of demonetisation , according to information compiled by the department.A new e-platform put in place by the Central Board of Direct Taxes, the apex tax authority, will be used to reach out to these account holders who will have to file their response online. “If the assessing officer requires more information, the assesse would be asked to submit them. The additional information will also be uploaded online. This is with the objective to bring about transparency,” said a city-based tax officer.In the course of a video-conference on Wednesday, CBDT members briefed senior officers of the I-T department about suspicious cash deposits, mobilisation target from the new declaration scheme, and the way to go about in taxing undeclared income that have found its way into banks.The 1,100 cases of search and seizure carried out by the tax department in the past two months have yielded around Rs 600 crore – of which Rs 150 crore is in new notes. About 1.5 lakh accountholders have deposited more than Rs 10 lakh each and there have been suspicious cash deposits in one crore accounts, belonging to 75 lakh people. Tax authorities believe that around Rs 1 lakh crore may be disclosed under the new income declaration scheme, which would result in tax collection of Rs 50,000 crore.“To begin with, the department will focus on the 1.5 lakh accounts with more than Rs 10 lakh deposits. This is the immediate priority and work will begin in the next few days,” said the official.The tax department of various circles – particularly Maharashtra, Gujarat, Tamil Nadu, and Karnataka – will also have to look into the huge cash deposits in some of the cooperative banks.“As expected, the tax department is increasing its reliance on technology to mine the huge amount of data in its possession, post demonetisation. This move will enable the department to channelise its energy into high-risk cases and nab the tax evaders more efficiently. As the tax department joins the dots by deployment of big data analytics, we expect substantial increase in enquiries/searches and assessments by the tax office,” said Amit Maheshwari, Partner Ashok Maheshwary & Associates LLP.Industry trackers say that in some cases, inquiries may have already begun. Since end-December, tax officials have been questioning instances of large cash deposits.“Income-tax department has already started raising queries where the money deposited is more than Rs 10 lakh as well as looking into large purchases made in old currency. Further, banks are required to furnish information to tax authorities in respect of cash deposit by end-January. Hence, many who deposited unusually large amounts of cash may receive tax notices as early as mid-February,” said Paras Savla, partner, KPB & Associates, a tax consultancy.The income-tax department is reportedly using data analytical tools to scan personal bank deposits to segregate black money holders from genuine taxpayers. The department had roped in consultants like Deloitte and EY for the analytics work. “These tools basically compares the bank-deposit data with the past income tax returns data and raises red flags wherever there are discrepancies,” said a person familiar with the exercise.