Russia’s Federal Security Service said on Monday that an attempt to kill General Vladimir Alexeyev was ordered by Ukraine’s security service, Russian news agency Interfax reported.

The agency added that Polish intelligence had taken part in recruiting the gunman, though the FSB did not provide evidence that could be independently verified.

Russian security officials said on Sunday that a Russian citizen of Ukrainian origin had been extradited from Dubai to Moscow on suspicion of being responsible for seriously wounding Alexeyev in the shooting.

There was no immediate comment from Ukraine or Poland on the allegations.