In 1979, a secretive lab in the Soviet city of Sverdlovsk accidentally released anthrax into the morning air, killing at least 67 people and countless other animals. The problem is, the Soviet Union was not supposed to have this anthrax. This was the single worst biological leak ever, one that almost exposed the Soviet's illegal biological weapons program. It was just bad meat from private butchers, the authorities claimed. It was not until 1992 onwards that the truth about the lab and the Russian biological weapons program would slowly leak out.

https://docs.google.com/document/d/1JDfwEiPdagop44-2Mehheu86JAh7vC7iEGy90_mKg3Q/edit?usp=sharing