Calcutta, Feb. 11 :    Calcutta, Feb. 11:  Howrah Municipal Corporation (HMC) is in trouble with the income-tax authorities over building plans sanctioned and trade licences issued over the past two years. Most of the buildings and highrises in the town have reportedly come up without sanctioned plans. The income-tax authorities on Monday asked the HMC to submit the past two years' returns, disclosing the number of building plans sanctioned, trade licences issued and payment made to the civic contractors. 'We can only account for payments made to the civic contractors over the past two years,' said HMC commissioner Chanchal Banerjee. Data on the number of building plans sanctioned and trade licences issued might be incomplete, he added According to HMC revenue department sources, there are over 67,000 buildings and 1,100 highrises, but the property tax bill is only Rs 4 crore. The figure should be Rs 50 crore. The difference is because most of the buildings and highrises have come up illegally and, hence, remain outside the dragnet of property tax. 'The state government is also losing revenue, as transactions in real estate go unregistered in most of the cases,' said an officer in the Howrah sub-registry office. However, Howrah will cease to be a tax haven, as mayor Gopal Mukherjee has asked the central valuation board to take up the tax revision process in the HMC. 'There has been no revision of property tax since 1984, though according to the HMC Act, it ought to have been revised every six years,' said the commissioner.