Bulgarian secret police used a KGB-designed poison-pellet umbrella gun to kill dissident emigre Georgi Markov in 1978. KGB assassin Boris Stashinsky used a poison gas gun to kill exiled Ukrainian nationalist leaders Lev Rebet and Stepan Bandera in the late 1950s. Another KGB assassin, Nikolay Khokhlov, was poisoned by radioactive thallium in 1957 after refusing an assignment and defecting to the West
In looking for info on this pen thing:
Image from "The Ultimate Spy Book" by H.Keith Melton. © 1996 DK Publishing.
Assassination gun
This silenced weapon was designed to be folded in a newspaper and fired from that concealment. The effect of its silencer is heightened by the fact that it is designed to be fired while pressed against the victim's body.
The KGB built both conventional and gas-firing versions of this weapon, which is similar to concealed and silenced weapons built during World War II.
Image from "The Ultimate Spy Book" by H.Keith Melton. © 1996 DK Publishing.
Poison-pellet weapons
Designed by the KGB, the poison-pellet umbrella was used in the assassination of Bulgarian dissident Georgi Markov in London. A jab with an umbrella at a bus stop -- easily dismissed as a meaningless accident -- delivered a pellet of ricin, a poison derived from castor-oil seeds. Markov was dead soon after.
Ricin is an extremely toxic poison; Scotland Yard estimated that only 425 micrograms of the poison killed Markov. It is also extremely difficult to detect in the bloodstream. Markov's assassination was detected only because the pellet carrying the ricin had not dissolved as expected.
The KGB also designed a pen-sized assassination weapon to deliver ricin pellets, one of a family of poison assassination pens that delivered gas or liquid poisons.
Cigarette case weapon
A cigarette case provided an excellent cover for this weapon, surrendered by KGB assassin Nikolai Khokhlov when he defected to West Germany in 1954. The device fired hollow-point bullets filled with poison through the false cigarettes at the opening of the case.
Khokhlov, sent to assassinate anti-Soviet emigre Georgi Sergeyvich Okolovich, defected rather than carry out his mission. Also in his possession were two miniature silenced pistols.
Suicide weapons
Throughout the Cold War, interrogation techniques reached ever-increasing heights of psychological, physiological and pharmaceutical sophistication. Despite the Hollywood fantasy of a heroic agent stoically refusing to answer questions under torture, it quickly became clear that no one could long withstand a technically skilled and ruthless interrogator.
Spies operating behind enemy lines might be called upon to make the ultimate sacrifice and kill themselves to avoid giving up vital information or compromising the safety of fellow agents.
Suicide weapons, easily concealable and quickly lethal, were developed as a last resort should capture become inevitable. Fast-acting poisons that killed within seconds could be delivered in the form of a capsule, a glass ampule full of liquid poison, or a poison-tipped pin.
Suicide weapons are a less-than-perfect defense and are only as effective as the resolve of the operative; at the show trial of downed U.S. pilot Francis Gary Powers, his poison pin was on display, debunking the U.S. claim that his was a weather flight.