Quantity of coal recovered from illegal mining has fallen 30% annually in FY18 to 17,603 tonne, coal minister Piyush Goyal said in Parliament on Tuesday. The data is according to the raids conducted by security personnel of CIL as well as joint raids with the law and order authorities of the concerned state governments. Coal India (CIL) has said that it is not possible to ascertain the exact quantum of coal stolen and losses incurred on account of theft\/pilferage and illegal coal mining. While recovery in West Bengal increased by 7% to 9,205 tonne, Jharkhand, the largest coal-bearing state, could redeem 7,440 tonne in FY18, a drop of 54%. Since law and order is a state subject, the responsibility of curbing illegal coal mining lies primarily with the state and district administration. The government has received no report about the coal mafia interfering in the management of government owned coal mines of CIL and its subsidiaries, Goyal clarified. The detection of illegal coal mining activities is mainly done at the Central Mine Planning and Design Institute, wherein satellite data is scanned to track coal mining activity taking place outside the authorised leasehold area.