The FSB reported to the press on Thursday that the action was to be carried out by an agent of Ukraine’s SBU commissioned by the Kiev government, and specified that the individual and four of his accomplices were arrested.

The executor of the planned attack, a Russian citizen born in 1978 recruited by the SBU, was arrested as he was taking two high-powered improvised explosive devices from a hiding place, the FSB said.

The detainee was found in possession of a phone that contained correspondence and conversations with a supervisor of the SBU, instructions to assemble the explosive device and transfer funds, and coordinates for the place of the attack.

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