Are there Chechen fighters in Ukraine?
29 May 2014 Last updated at 19:05 BST
Reports suggest Chechen fighters are being sent to eastern Ukraine to support pro-Russian militia there.
Chechnya's Moscow-backed leader Ramzan Kadyrov has denied sending his troops, but he said there could well be Chechen volunteers fighting against the Ukrainian army.
BBC Russian's Olga Ivshina reports from Donetsk.