Vote counting is under way in Nigeria's tightest presidential election since military rule ended in 1999. Saturday's voting was marred by long delays at polling stations, as well as scattered reports of ballot box snatching and attacks by armed men. And some parties have raised alarm over allegations of irregularities, which could lead to a disputed outcome. Tens of thousands of polling stations are counting the results, which will be collated and sent to the electoral headquarters in the capital, We spoke to Lenny Taaba from the Electoral Institute for Sustainable Democracy in Africa - EISA.