Tanzanians protest at delay announcing election results
Opposition supporters have held protests in several parts of Tanzania at the slow pace of announcing the result of Sunday's general election.
Police fired tear gas in Mwanza, while there have also been protests in parts of Dar es Salaam and Zanzibar.
The head of the election commission told the BBC that the problems have occurred in a small number of areas and overall, the vote passed off smoothly.
President Jakaya Kikwete says he is confident of winning.
But he faces a strong challenge from former priest Willibrod Slaa and university professor Ibrahim Lipumba, among six opposition candidates.
Voters were also electing 239 members of parliament.
A few parliamentary results have been announced but supporters of Mr Slaa in the main city, Dar es Salaam, said some had been rigged in favour of Mr Kikwete's CCM party which has governed since independence.
Police fired water cannon to disperse opposition protesters, who had blocked roads with burning tyres in the Tandika suburb of Dar es Salaam.
Voting passed off peacefully on Sunday in the Indian Ocean archipelago of Zanzibar, which has witnessed fierce clashes in previous elections.
But on Monday the BBC's Jamhuri Mwavyombo says large crowds gathered outside the local election commission offices, chanting and praying on the mainly Muslim island.
This was the first election since the two main parties agreed to share power on the islands.
Despite the calls for the results to be announced more quickly, Tanzania's national Electoral commission chairman Lewis Makame told the BBC's Focus on Africa programme that final results would be declared on Friday "at the earliest".
He admitted some problem had occurred but said: "Those things which have gone wrong are a small proportion in comparison to the enormity of the task we are carrying out."
President Kikwete, of the governing CCM party, was elected with more than 80% of the vote in 2005 and is now expecting to win again.
Mr Kikwete promises to reduce poverty, improve health, education and transport, says the BBC's Josphat Makori in Dar es Salaam.
But Mr Kikwete's critics accuse his government of not living up to similar pledges during his first term, our correspondent says.
More than 50% of Tanzanians still live below the poverty line, according to the International Monetary Fund.