UN officials sent troops to the garbage dump a few kilometres north of the capital, Port-au-Prince, to recover the election material, according to David Wimhurst, a UN spokesman, who called the discovery "extraordinary".
On Wednesday, Associated Press journalists saw hundreds of empty ballot boxes, at least one vote tally sheet and several empty bags, numbered and signed by the heads of polling stations, strewn across the fly-infested dump.
Leading candidate Rene Preval has alleged that election officials have undercounted his support in an effort to prevent him from winning a first-round victory.
He said that "massive fraud or gross errors" tainted the results of the 7 February vote.
Results released so far showed Preval, a former Aristide protégé who also has strong support among Haiti's poor majority, was just short of the majority needed for a first-round presidential victory.
A wave of chaotic protests by Preval supporters sent foreign diplomats scrambling for peaceful solutions. Preval has urged them to continue protesting, but to avoid violence.
Ambassadors from countries "directly involved in the crisis" were discussing a Brazilian plan to persuade the other candidates to recognise Preval's victory and thus prevent a mass uprising, according to Marco Aurelio Garcia, foreign affairs adviser to Luiz Inacio Lula da Silva, the Brazilian president.
Preval (L) has strong support
among Haiti's poor majority
In New York, the UN Security Council urged Haitians to respect election results and refrain from violence, and it extended the Brazilian-led UN peacekeeping mission in Haiti for six months, until 15 August.
Haiti's interim government had ordered the count suspended with 90% of the votes tallied, pending a review of vote tally sheets by an investigative commission representing the president's office, the electoral council and Preval's party.
Michel Brunache, chief of staff of Boniface Alexandre, the interim president, said: "We are looking closely at specimens of the ballots found at the dump, to check whether these are real ballots."
He said the ballots were being examined by the judiciary, because the investigating commission had not yet been formed.
Government order ignored
But Max Mathurin, the electoral council president, said Wednesday that election workers are ignoring the government order and continuing to tabulate results.
"The government and the established commission can't under any circumstances ask or order the cancellation of the operations."
Workers have completed 92% of the vote count, he added, while refusing to release any more information.
Mathurin said: "When everything is ready, we're going to publish the official results."
He denied that the electoral council had manipulated the vote count.
Hours earlier, the local Telemax TV news broadcast images from the dump showing smashed white ballot boxes with wads of ballots strewn about.
Ballot after ballot was marked for Preval.
Among the bags seen by AP was one vote tally sheet from the Port-au-Prince neighbourhood of Carrefour that recorded 129 votes for Preval out of 202 cast.
Someone had tried to burn the
boxes, a witness said
Jean-Ricot Guerrier, a man picking through the dump, said a truck dumped the material a day after the election.
Someone tried to burn the material, but rain put out the fire, he said.
Wimhurst said the ballots could have come from any of nine polling stations across the country that were ransacked on election day, forcing officials to throw out up to 35,000 votes.
At least one voting centre was destroyed by people tired of waiting in line, others were destroyed by political factions, he said.
Both Wimhurst and Mathurin raised the possibility that someone dumped the ransacked ballots to create an appearance of fraud, and Mathurin said UN troops would be responsible for any unprotected ballots.