Front-runner René Préval on Tuesday decried ”massive fraud or gross errors” in Haiti’s presidential election, insisted he won outright, and urged supporters to continue protesting. The presidency promptly announced the formation of a commission to investigate the claims and called for final results of the February 7 election to be kept under wraps until the probe is completed.

René Préval (63) was expected to appeal for calm in Haiti on Tuesday following protests over a vote count that put him short of the 50% he needs to be elected president in the first round. Tension remained high as Préval’s supporters insisted the frontrunner be declared president, despite the partial results.

Haitians on Sunday nervously awaited the final outcome of presidential polls, and authorities called for calm after René Prevál, a champion the poor, fell below the 50% needed to win outright. With one fourth of the ballots still to be counted, Prevál, a former president, dominated the vote, but with 49,1%, he was almost one point short of the majority he needs to avoid going to a second round.

René Préval, who took an huge early lead in Haiti’s presidential elections, is a former ally of Jean-Bertrand Aristide, though he has distanced himself from the former president who fled in 2004. Préval took over 61% of the vote with 15% of the ballots counted, more than 48% ahead of his closest rival.