Congo's first elected prime minister was Patrice Lumumba who was immediately faced with a breakdown of order. There was an army revolt while secessionist groups from the mineral-rich province of Katanga made their move and Belgian paratroopers returned, supposedly to restore security.
Lumumba made a fateful step - he turned to the Soviet Union for help. This set off panic in London and Washington, who feared the Soviets would get a foothold in Africa much as they had done in Cuba.
In the White House, President Eisenhower held a National Security Council meeting in the summer of 1960 in which at one point he turned to his CIA director and used the word "eliminated" in terms of what he wanted done with Lumumba.
The CIA got to work. It came up with a series of plans - including snipers and poisoned toothpaste - to get rid of the Congolese leader. They were not carried out because the CIA man on the ground, Larry Devlin, said he was reluctant to see them through.
Murder was also on the mind of some in London. A Foreign Office official called Howard Smith wrote a memo outlining a number of options. "The first is the simple one of removing him from the scene by killing him," the civil servant (and later head of MI5) wrote of Lumumba, who was ousted from power but still considered a threat.
MI6 never had a formal "licence to kill". However, at various times killing has been put on the agenda - but normally at the behest of politicians rather than the spies.
Anthony Eden, prime minister at the time of Suez, had made it clear he wanted Nasser dead and more recently David Owen has said that as Foreign Secretary, he had a conversation with MI6 about killing Idi Amin in Uganda (neither of which came to anything).
But in January 1961, Lumumba was dead.
Did Britain and America actually kill him? Not directly. He went on the run, was captured and handed over by a new government to a secessionist group whom they knew would kill him.
The actual killing was done by fighters from the Congo along with Belgians- and with the almost certain connivance of the Belgian government who hated him even more than the American and the British.