CHENNAI: The Directorate of Vigilance and Anti-Corruption (DVAC), registered a criminal case against ex-AIADMK Minister for Rural Development and presently Member of Tamil Nadu Legislative Assembly SP Velumani based on allegations that he had abused his official position in awarding tenders injudiciously to his close associated companies causing loss to the government exchequer approximately Rs 500 crore in replacing the existing street lights with LED lights in rural areas during the period from 2015 to 2018.