The Ukrainian Interior Ministry has information that the Russian special services are planning to kill the leaders of militants as unwanted witnesses, an adviser to the Ukrainian interior minister, Zorian Shkiriak, has said.

''Based on the information we have received, we can assume that the Kremlin is ready to 'shoot' some leaders of Russian terrorist groups operating in Donetsk and Luhansk regions of Ukraine," he told Interfax-Ukraine on Tuesday.

He said that first and foremost, the issue concerns FSB (Federal Security Service) and GRU (Main Intelligence Directorate) officers, militants Igor Girkin-Strelkov ("Strelok"), Igor Bezler ("Bes") and one of the leaders of the self-proclaimed Luhansk People's Republic, Valeriy Bolotov.

"The only one of the terrorist leaders who retains the possibility of returning to Russia is Borodai as the Kremlin's personal political strategist," Shkiriak said.

The Interior Ministry said that after a "monstrous terrorist attack against the Malaysian Boeing over Torez" committed by Russian military air defense experts, together with Bezler's militants, "these people have become unwanted carriers of impressive compromising evidence against the Russian president''.

Shkiriak said that Russian border guards had been ordered not to allow militants to enter Russia and kill them if they attempt to cross the border. He recalled that cases of such mass executions of separatists by defensive squads of the Russian border troops on the Ukrainian-Russian border had already been reported.