SOCHI - AN AMERICAN journalist with the New Yorker magazine was briefly arrested at a polling station in the Russian city of Sochi on Sunday, Ria-Novosti news agency reported.

Keith Gessen was arrested during a mayoral vote here, which is being seen as a test of Moscow's democratic credentials.

He was detained when he turned up with opposition candidate Boris Nemtsov, a former deputy prime minister who is now a prominent Kremlin critic.

According to an official from the local electoral commission, cited by the news agency, Mr Gessen was carrying neither a press card nor accreditation allowing him access to cover the vote. After his passport and identity had been checked, Mr Gessen was released, Ria-Novosti said.

The Black Sea city has been placed under the media spotlight since it won a bid to host the 2014 Winter Olympics.

Ahead of the gamed the city is expected to see US$12 billion (S$18 billion) worth of investment. Mr Nemtsov's campaign said the journalist was the victim of a bureaucratic mix-up.

Late on Sunday, a commission official told AFP that the pro-Kremlin candidate was way ahead in voting with four fifths of ballots counted.

Incumbent Anatoly Pakhomov, standing for Prime Minister Vladimir Putin's United Russia Party, had picked up 'almost 77 per cent of votes cast,' an official with the electoral commission told AFP.

Mr Nemtsov was running at 13.5 per cent in the palm-tree lined coastal resort, where Mr Putin regularly goes skiing.

At the start of the campaign, more than 20 candidates had declared their hand, including a porn star, a ballet dancer, a press magnate and a former KGB agent.

But most gradually dropped out and opposition candidates who remained complained about irregularities including the refusal of local media to run their political advertisements. According to official figures earlier on Sunday, the turnout was about 38 per cent of the electorate. -- AFP