Zimbabweans are voting in a presidential election that has already been hit by allegations of fraud.
On Tuesday, incumbent Robert Mugabe said he would resign after 33 years in power if he lost.
It came as Prime Minister Morgan Tsvangirai’s Movement for Democratic Change (MDC) accused Mr Mugabe’s Zanu-PF of doctoring the electoral roll. Zanu-PF denied the accusation.
Campaigning has been peaceful, with no reports of violence or intimidation.
The last presidential poll five years ago were overshadowed by myriad problems, including violence.
Voting began at 07:00 (05:00 GMT) and is scheduled to end at 19:00 (17:00 GMT), with results expected within five days.
The situation has been relatively calm ahead of the poll, with most bars in the capital Harare full on Tuesday night, given that Wednesday was declared a holiday to allow for voting, the BBC’s Brian Hungwe reports from Harare.
Amongst the topics discussed by Harareans on the eve of the poll was the conduct of parties before the elections, and the political implications of victory or defeat for Mr Mugabe, our correspondent adds.
A large turn out is expected, given the tens of thousands of people who have gone to rallies staged by the candidates in recent weeks.
