Stock market benchmark indices went into a tailspin in early trade after US President Trump's tariff hikes and retaliation from China fanned fears that a full-blown trade war will impact economic growth. The 30-share BSE benchmark Sensex crashed 3,939.68 points or 5.22 per cent to 71,425.01 in early trade. The NSE Nifty tumbled 1,160.8 points or 5.06 per cent to 21,743.65.