The Gujarat Anti-Terrorism Squad (ATS) has frozen assets worth Rs 3.13 crore of four men booked under the Narcotics Drugs and Psychotropic Substances (NDPS) Act, an official statement said on Saturday. Around 225 kg of mephedrone (MD) worth Rs 1,125 crore was seized and six persons were accused of manufacturing the drug at a chemical factory, named Nectar Chem, in Moski village in Savli taluka of Vadodara, officials said. The crackdown was carried out as a part of a joint operation of the Gujarat ATS and the state police. Assets gained through alleged illegal drug trade worth over 3 crore of four accused - Rakesh alias Rako Narsibhai Makani, Vijay Odhavji Vasoya, Piyushbhai Ashokbhai Patel and Mahesh alias Mahesh Dhoraji - have been seized under Section 68F of the NDPS Act, as per officials.