New Delhi, Jan. 31 -- The Narcotics Control Bureau (NCB) has busted a secret mephedrone manufacturing laboratory, which was being run under the cover of a cleaning solvent factory, in Karnataka's Mysuru and arrested four people, including the kingpin, the agency said in a statement on Friday, adding that it has seized drugs worth Rs.10 crore. The lab was being run by the four accused, all from Jalore district of Rajasthan, since 2024. According to NCB, the operation came to light when 35kg of mephedrone was found in a car with a Karnataka registration number, which was intercepted in Palsana in Gujarat's Surat district on January 28. "A search at the house of Mahindra Kumar Bishnoi, mastermind of the drug network in Dastan Residency, Palsana, led to the recovery of 1.8kg of opium, cash amounting to Rs.25.6 lakh and various chemicals. htc...