The Indian rupee tumbled sharply to crash beyond Rs 91 per dollar mark on Tuesday tracking muted local equities and risk averse sentiments. Lingering uncertainty around tariffs coupled with persistent foreign portfolio outflows weighed on the local unit. The Indian rupee extended its losing streak for the fourth trading day, hitting 91-per-dollar for the first time as the government tabled a bill in Lok Sabha to raise FDI in the insurance sector to 100 percent. At the time of writing, the benchmark BSE Sensex dropped 533.50 points, or 0.63 percent, to 84,679.86, extending the previous session's decline amid weakness in metal and financial shares. The broader NSE Nifty index fell 167.20 points, or 0.64 percent, to 25,860.10.