By Devidutta Tripathy NEW DELHI (Reuters) – Indian mobile phone market leaders Bharti Airtel and Vodafone bought airwaves worth about $3 billion each in a hotly contested auction that raised nearly $10 billion, far exceeding the governments target. No.1 Bharti and second-ranked Vodafone said they had won airwaves in the premium 900 megahertz band that was available in three key cities — Delhi, Mumbai and Kolkata. Conglomerate Reliance Industries, a new entrant in telecoms that is seen as a threat to the incumbents, bought airwaves in another band in 14 locations the government said, estimated to have cost it $1.7 billion. The market leaders heavy spending on airwaves underscores the fierce competition and their bet on mobile data in the worlds second biggest mobile phone market behind China.