An oil pipeline has been damaged by an explosion in the southern Russian republic of Dagestan, close to the Chechen border.
There were no casualties and firefighters extinguished the blazing oil after about two hours.
The cause of the explosion was not known but officials said it could have been a bomb.
The pipeline, which carries Caspian sea oil from Baku in Azerbaijan to Novorossiisk in Russia, has been damaged frequently by armed gangs from Chechnya and individuals seeking to steal oil.
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