The Income Tax department today surveyed business premises of big onion and vegetable traders including at Azadpur wholesale market here to detect hoarding and illegal profiteering.

IT sources said the officials of the IT department began an early morning operation of checking and obtaining the account books and ledgers of large wholesale onion traders based in Delhi and NCR.

The department's action was to crackdown on hoarding and over-valuation of onion stocks, they said.

The I-T department had last week conducted similar survey operations in Uttar Pradesh, Maharashtra and few other states.

Meanwhile, traders in Maharashtra's Nashik and adjoining onion-growing areas today went on two-day strike against I-T raids and disrupted supply to traders from other states who are being forced to sell the vegetable at "below the cost price".

Finance Minister Pranab Mukherjee had earlier said I-T raids in the premises of different traders have also helped in reducing onion prices.

There has been a "dip in onion prices in some states after I-T search," he had said.

The retail price of onion has started easing but still it continued to rule high at Rs 55-60/kg in metros after nationwide raids and increased supply from growing states.

Food inflation has crossed over 18 per cent for the week ended December 25 due to high rates of onion and other items.

Due to crop damage in key growing states, the country's total onion production is expected to decline by 12.5 per cent to 10.5 million tonnes this year against 12 million tonnes in 2009-10, according to research body NHRDF.