International observers say the hardline leader of Belarus has won re-election once again through fraud and violence after more than 16 years of repressive rule.
Election observers and Western governments said President Alexander Lukashenko's success had been seriously flawed.
The country's election commission declared that Mr Lukashenko got almost 80 per cent of the vote in a preliminary count, handing him a fourth term in office.
But the Organisation for Security and Co-operation in Europe said the count in yesterday's vote was "bad or very bad" in half the country's districts.
It also strongly criticised the violent dispersal by riot police of a post-election protest rally. US and European leaders criticised Mr Lukashenko for a wave of violence directed at rival presidential candidates and their supporters in the hours after the election.
Mr Lukashenko's continuing grip on power makes Belarus one of the last relics of Soviet-style dictatorship, a nation of 10 million on the edge of Europe with overwhelming state control of politics, industry and media.
The country's continuing repression has been an embarrassment to the European Union, which offered 3bn euros in aid to Belarus if the elections were judged to be free and fair.
Despair and anger gripped many in the country today.
"Lawlessness, dictatorship – what else can you call this?" said Natalia Pohodnya, waiting in the snow outside a Minsk jail where her son was being held after participating in a demonstration. "They are beating our children!"
There were no signs of imminent unrest in Minsk's centre of wide streets lined with Stalin-era buildings. The riot police had vanished by dawn.
The run-up to the election had raised a glimmer of hope that Mr Lukashenko was relaxing his grip. The number of candidates was unprecedented, they were allowed comparative freedom to campaign and were even allotted time for debates on state media. Belarus had also passed some reforms in its election code.
But evidence of fraud before and during the vote drove tens of thousands of protesters into the streets at night to denounce alleged irregularities. Helmeted riot police bearing shields and swinging truncheons dispersed the protesters from near the main government building after some in the crowd broke windows and doors. Police also arrested seven of the nine candidates opposing Mr Lukashenko.
"A positive assessment of this election isn't possible," said the OSCE observer mission's head, Geert-Hinrich Ahrens.
One of the top opposition candidates, Vladimir Neklyayev, was beaten in a clash with government forces as he tried to lead a column of supporters to the protest. He was taken to a hospital, but his aide said seven men in civilian clothing later wrapped Mr Neklyayev in a blanket on his hospital bed and carried him away as his wife screamed.
Mr Lukashenko, a 56-year old collective farm manager, has allowed no independent broadcast media, kept 80 per cent of industry under Soviet-style state control and suppressed opposition with police raids and pressure.
But his efforts to maintain a Soviet-era social safety net have kept him popular with some elderly people nostalgic for the certainties of the Soviet era.
But in recent years, he has argued intensively with the Kremlin, his main sponsor, as Russia raised prices for the gas and oil on which Belarus depends.
Mr Lukashenko also had been working to gain favour with the West, releasing some political prisoners and making Belarus part of the European Union's Eastern Partnership initiative.
However, his tone changed this month after Russia agreed to drop tariffs for oil exported to Belarus – a concession worth billions a year.
And the tainted vote and violent dispersal of opposition protests make any further rapprochement with the West unlikely.