Russia has had a poisons laboratory since the time of Lenin or before. Enemies of state or enemies of Putin are sometimes poisoned to make a statement. Others are killed the old-fashioned way, with a bullet to the head. An interesting poison in the Kremlin arsenal is applied to the outside of a light bulb. When the light bulb heats up, the poison is released to the air and anyone nearby dies. Collateral damage is not important.
Trump must go