Reports say that a Russian hostage in Chechnya has been released in exchange for a Chechen prisoner in Russia.

The hostage -- a Russian police officer, Sergei Khalansky -- had been held since June by his kidnappers who had demanded a large ransom.

His release was negotiated by the governor of the Siberian region of Krasnoyarsk, Alexander Lebed.

Mr Lebed -- a former general and potential presidential candidate -- was instrumental in the negotiations in 1996 that ended Chechnya's war for independence from Russia and since then has helped secure the release of other Russian hostages.

Correspondents say that hostage-taking for ransom has become a booming business in the Russian breakway republic and that more than a hundred Russian and foreign hostages are believed to be still held there.

Four Western hostages - three Britons and a New Zealander -- were beheaded by their kidnappers earlier this month after a rescue attempt went wrong.