MUMBAI (Reuters) - Hindalco Industries Ltd
The company, controlled by billionaire Kumar Mangalam Birla, shut the plant on May 7 for maintenance, exacerbating a shortage that began in late March after rival Sterlite Industries
Hindalco's Birla smelter and Sterlite's Tuticorin smelter account for about 90 percent of India's total copper output of 690,000 tonnes.
(Reporting by Prashant Mehra, editing by Anurag Kotoky)