The rupee plunged 26 paise to 83.40 against the US dollar in early trade on Tuesday as initial counting for the Lok Sabha elections indicated a mixed trend. A weak trend in domestic equity markets also dented sentiments in early deals, forex traders said. According to television reports, the BJP-led NDA surged ahead with leads in more than 200 parliamentary seats out of 350 for which trends were available, with the opposition INDIA bloc ahead in 120. Counting of votes for the Lok Sabha elections began on Tuesday morning across states and Union Territories. At the interbank foreign exchange market, the local unit opened weak at 83.25 and lost further ground to trade at 83.40 against the greenback in initial deals, registering a fall of 26 paise from its previous close. On Monday, the rupee closed at 83.14 against the US dollar. Meanwhile, the dollar index, which gauges the greenback's strength against a basket of six currencies, was trading 0.05 per cent lower at 104.02. Brent cr