Haiti's first election since former President Jean-Bertrand Aristide was ousted in February 2004 has been marred by angry demonstrations in the capital.
Voters vented their anger as some polling station opened late
Polls closed after voting was extended following some polling stations in the capital's failure to open on time, which lead to shoving and stampedes.
Voters were choosing a new president, as well as a 129-member parliament.
The front-runners are Rene Preval, a former ally of Mr Aristide, and Charles Henry Baker, a businessman.
Officials results are expected on Friday.
When polling stations failed to open, angry voters tried to force their way in. At least one man was reported to have died in the crush in a Port-au-Prince district, and several others were injured.
Some protesters claimed the delays were part of a concerted attempt to stop people in poor areas from voting for Mr Preval.
The electoral authorities denied this, and appealed for calm.
Rene Lucas, from the impoverished slum of Cite Soleil, said: "If we are not able to vote today we will be in a state of crisis for the next five years".
Thousands of armed UN troops were deployed to watch over the election process, which has been delayed several times.
Despite the presence of peacekeepers, the country has continued to be blighted by political and criminal violence and instability.
Former President Preval, 63, is a long-time ally of Mr Aristide who is popular with the poor.
Mr Baker and former President Leslie Manigat are considered his closest rivals.
Some of Haiti's 3.5 million registered voters live some way from a polling station.
Auxilien Jean Dieudonna, waiting at a polling station in Port-au-Prince, told the BBC that he had left his house in the mountains at midnight and walked for more than four hours to take part.
"I came to vote for my charismatic leader [Rene Preval] so that he can run my country," he said.
If none of the candidates achieves a 50% majority first time round, the two best-placed candidates will compete in a run-off.
Mr Aristide was first elected in 1990, but within a year he was overthrown, and replaced by a succession of military governments.
The US, backed by the UN, intervened in 1994 to restore order.
Some voters travelled for hours to get in line to cast their ballot
In the elections that followed Mr Aristide was barred from standing, but Mr Preval, his close ally, took nearly 90% of the vote.
Mr Aristide later returned to power, but he was forced out in early 2004 when opposition to his rule grew increasingly violent. He remains in exile in South Africa.
Mr Preval has told the BBC that Mr Aristide may return if he wishes, but that he will not tolerate the violent groups that pledge him allegiance.