A team deployed from the Metropolitan Police Crime Division had nabbed the 47-year-old after some fuel station operators revealed that he was involved in black marketing, taking advantage of the ongoing crisis.A permanent resident of Sonigama-6 of Dhanusha district, Sah earlier had served as the Director General of Nepal Bureau of Standards and Metrology. Police said they arrested a senior government official for his alleged involvement in black marketing of petroleum products.Joint-Secretary at the Ministry of Science Technology and Environment Ram Aadhar Sah was arrested from Gaushala of Kathmandu on Sunday evening.Nepal is currently reeling under fuel crisis due to blockade at Nepal-India border for over three months