Equity markets plunged as Nifty fell 1.64% to 23,063.10 and Sensex dropped 1.67% to 73,580.54, marking their steepest single-session fall since July 8. The rupee weakened 23 paise to 95.96 per dollar as Brent rose to $105.6 after Iranian remarks, reviving inflation and supply concerns. The sell-off was broad-based, hitting all major sectors, small- and mid-caps, banks and financials.