Voting is taking place in Angola in the first parliamentary polls for 16 years.
Although 14 parties are taking part, the contest is primarily between long-term rivals, the ruling MPLA party and opposition Unita party.
Some delays were reported as voting began, and an EU election observer told the BBC that in parts of the capital, Luanda, voting procedures were chaotic.
The poor but oil-rich nation has been at peace for six years, when 27 years of conflict came to an end.
As the election got under way, people were reported to have begun queuing at polling stations in Luanda.
Among those to vote in the capital early on Friday was President Jose Eduardo dos Santos.
But the head of the EU observer mission, Luisa Morgantini, said voting in parts of Luanda had been disorganised.
“The way in which on the ground things work in Luanda or at least in parts of Luanda is quite problematic,” she told the BBC’s Network Africa programme.
Some eight million voters are registered in the country – more than a quarter of whom live in the capital’s very overcrowded conditions.
The MPLA, which is the dominant political force in the country, is widely expected to win the election and consolidate its hold on power.
The party is using the poll as a dress rehearsal for next year’s planned presidential election, the BBC’s Peter Biles in Luanda says.
The president has already been in power for nearly 30 years – longer than Zimbabwe’s leader Robert Mugabe.
But our correspondent also says there is enormous hope that Angola can be set on a new path, and that democracy and stability can be reinforced.
In the lead up to the election, Unita accused the MPLA of intimidating its supporters and dominating state media.
Thursday was the first day in a week that the state newspaper Jornal de Angola carried no front-page picture of Mr Santos.
But Caetano de Sousa, head of Angola’s electoral commission, said there had been a level playing field.
“The electoral campaign was carried out throughout the country under equal circumstances for all candidates,” he said.
He warned the parties to accept the result, saying they had a “moral, social and political duty to safeguard the peace and stability”.
These elections are an important move to consolidate democracy in sub-Saharan Africa, after the troubles in Kenya and Zimbabwe this year, our correspondent says.
Angola’s last election in 1992 sparked the second phase of the country’s 27-year civil war, which ended in 2002.