February 26 incident

The was an attempted "coup d'état" in the Empire of Japan on 26 February 1936. It was organized by a group of young Imperial Japanese Army (IJA) officers. They wanted the purging the government and military leadership because of bad economic policies.
During this incident, the rebels assassinated two former prime ministers and occupied the government center of Tokyo. However, they failed in assassinating Prime Minister Keisuke Okada or take control of the Imperial Palace. With a lot of opposition against them, the rebels surrendered on 29 February.
This was the last time that a former prime minister was assassinated until Shinzo Abe's assassination in 2022.