They say unregulated development, and fighting between separatists and the Russian army, has destroyed Chechnya's rich natural habitat.

Rivers are badly affected, with widespread oil spills and pollution from sewers damaged by war.

There are also concerns over the impact of illegal logging in Chechen forests.

The World Wildlife Fund said illegal logging is destroying the republic's dense mountain forests.

Forest guards have died in areas around the capital, Grozny, because of large numbers of land mines, officials said.

"Environmental monitoring in Chechnya, especially in the rivers and other bodies of water, shows their terrible state, particularly due to leaking oil pipelines and a sewerage system that has not worked for years," a state environment official told the AFP news agency.

There is also concern over chemical and radioactive pollution, as a result of the bombardment of chemical laboratories during the conflict.

Figures compiled by Chechen doctors show a growing number of genetic abnormalities in babies and unexplained illnesses among schoolchildren.