Riot police in Azerbaijan using tear gas and dogs, have clashed with thousands of opposition supporters after the son of ailing leader Mr Haydar Aliyev won a presidential election.
At least one man died in the violence. Medics found his body covered in blood outside a clinic in Baku.
Within hours of Mr Ilham Aliyev's victory, which sealed the first dynastic succession in an ex-Soviet state, about 3,000 opposition activists surged towards a square holding government buildings, hurling stones and overturning cars.
Supporters of opposition candidate Isa Gambar chanted "Isa! Isa!" and banged truncheons and shields stolen from police. Officers advanced on the crowd, and after 20 minutes of running battles, the square was emptied. Medical teams said about 50 protesters were injured.
The election's outcome will reassure investors keen to ensure stability in the oil- and gas-rich country, which was jolted by turbulent politics and bloodshed at the end of the Soviet era following the fall of communism.
But the violent protest highlights the concerns of opposition figures and rights groups who accuse the outgoing president of tolerating widespread abuses and corruption.
His son promised stability for his eight million people and vowed to pursue the policies of his father, the dominant force in the Caspian state since the 1960s and viewed by Western companies as the guarantor of order and prosperity.
With 91 per cent of votes counted, election officials said Ilham had won 79.5 per cent, far ahead of Gambar's 12.06 percent.
The Organisation for Security and Cooperation in Europe , a human rights and democracy watchdog, said the election was punctuated by violence, intimidation, ballot-stuffing and media bias.
"What we observed was an electoral process falling short of international standards in several respects," said Mr Giovanni Kessler, head of the OSCE observation mission in Azerbaijan.
He told a news conference opposition rallies and meetings had been tightly restricted and state-controlled media had not granted equal time to opposition candidates.