MUMBAI: The Indian central bank likely intervened heavily just before the close of the local spot market on Friday, five traders told Reuters, which lifted the rupee firmly past the 90 per dollar mark and helped it post its best one-day gain in three years. The rupee closed at 89.27 per U.S. dollar, up 1.1% on the day after hovering near 90.20 minutes before the local spot market closed at 3:30 P.M. IST. Indian Rupee soars past 90 per dollar as central bank reprises heavy-handed defence Traders pointed to very heavy dollar sales from a large state-run bank, most likely on behalf of the Reserve Bank of India. It seems “the RBI wanted to break the back of speculators completely,” a trader at a Mumbai-based bank said, referring to those wagering against the rupee.