President Alexander Lukashenko of Belarus is seeking a sixth term in office in an election he is both tipped to win but which is also likely to be his toughest challenge yet.
He won previous elections by a landslide but the votes were condemned by election observers.
This time though he has a prominent rival in a 37-year-old who is running in place of her jailed husband.
Belarus has also seen large opposition protests and a row with Russia.
President Lukashenko, 65, and sometimes referred to as Europe's last dictator, was first elected in 1994.
In the last vote in 2015, he was declared winner with 83.5% of the vote. There were no serious challengers and election observers reported problems in the counting and tabulation of votes.
So will this vote be different?
Probably not. President Lukashenko is widely expected to win again. But the vote is being closely watched amid growing signs of frustration at his leadership.
The campaign has seen the rise of opposition candidate Svetlana Tikhanovskaya, a former teacher who became a stay-at-home mother until thrust into the political spotlight.
Her husband was arrested and blocked from registering for the vote so she stepped in to take his place.
"People are waking up, rediscovering their self-respect," she told AFP in a recent interview. But she also said she expected the election to be rigged.
President Lukashenko has dismissed Ms Tikhanovskaya as a "poor little girl", manipulated by foreign "puppet masters".
Tens of thousands defied an escalating crackdown on the opposition last month to attend a protest in the capital Minsk last month, the largest such demonstration in a decade.
Hundreds of protesters have been held since May, human rights activists say.
On the eve of the vote Ms Tikhanovskaya's team said her campaign manager had been arrested and would not be released until Monday.
Is anyone else running?
There are three other candidates:
- Anna Kanopatskaya, a former MP who won a rare seat for the opposition in parliamentary elections in 2016
- Sergei Cherechen, the leader of the Social Democrat party
- Andrei Dmitriyev, the co-chair of the Tell the Truth movement, a campaign group which has been raided by the authorities
Two key opposition figures were barred from running and threw their weight behind Ms Tikhanovskaya's campaign.
Noisy defiance as election looms
By Abdujalil Abdurasulov, BBC News, Minsk
The calm streets of Minsk sporadically burst with the noise of drivers honking their car horns. Some flew a flag with a red stripe on the white background – the symbol used by the opposition.
Voicing dissent is dangerous in Belarus but activists still make noise despite a crackdown. People can be detained even for playing the wrong music, as happened to two DJs at a government-sponsored event in Minsk earlier this week.
It is this defiance that is making the election if not unpredictable then at least the most challenging for Aleksander Lukashenko.
Since the start of the election campaign in May, more than 2,000 people have been detained, according to Human Rights Centre Viasna.
Early voting began on 4 August and monitoring groups say their volunteers have frequently been prevented from observing the vote and even arrested.
Rumours have spread widely that the government is going to shut down mobile networks on Sunday Read More – Source