UPDATE 1-Belarus hands over alleged mercenaries to Russia - Russian prosecutor

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MOSCOW, Aug 14 (Reuters) - Belarus has returned a group of 32 Russian nationals to Russia after detaining them and accusing them of being mercenaries, the Russian General Prosecutor's Office said in a statement on Friday.

Belarus arrested the men last month and said they had sought to destabilise the country prior to Sunday's presidential election.

Russia dismissed that accusation and described the men as employees of a private security firm. Moscow said the men were only passing through the Belarusian capital of Minsk on their way to other countries and that they had been wrongly detained.

Ukraine had sought the extradition of 28 of the alleged mercenaries whom it suspects of fighting alongside Russian-backed separatists in eastern Ukraine.

Belarus had said it would cooperate with Ukraine in the case. (Reporting by Gabrielle Tétrault-Farber Editing by Tom Balmforth and Frances Kerry)