A 93-year-old Belgian former diplomat who this year became the first person charged in the fateful assassination of Congolese independence ​leader Patrice Lumumba in 1961 died on Monday before he could stand trial.

The death of ‌Etienne Davignon, an aristocrat who served as a European commissioner in his decades as one of Belgium's leading diplomats and industrialists, was confirmed by the Jacques Delors Institute think tank, where he served on the board.

Davignon ​had been ordered to stand trial for war crimes for alleged involvement in Lumumba's killing ​65 years ago, a final attempt to shed light on one of ⁠the 20th century's most consequential political assassinations.

Lumumba, who became prime minister of the country now ​called the Democratic Republic of Congo upon independence from Belgium in 1960, was ousted months ​later and killed by Belgian-backed secessionist rebels on January 16, 1961.

The murder was a dark chapter in Belgium's colonial history and a watershed for African countries' liberation struggles.

Prosecutors said Davignon, a junior diplomat at the ​time, had participated in Lumumba's unlawful detention or transfer and deprived him of his right to an ​impartial trial.

Davignon was also accused of involvement in the murders of two of Lumumba's political allies, Maurice ‌Mpolo ⁠and Joseph Okito. He had denied any wrongdoing and at the time of his death was awaiting the outcome of an appeal against his referral to trial.

Davignon was the last person still alive being investigated in a case opened almost 15 years ago. The court ruled that cases against ​other suspects would not remain open after ​they died.

The Lumumba family ⁠said the decision from prosecutor and tribunal that the case merited trial was now a matter of record, adding: "The last living accused ​does not close the historical record."

Their attorneys said in a statement they ​were preparing ⁠further legal actions such as a civil complaint against the Belgian state.

After his Congo assignment, Davignon rose to become a leading figure in the Belgian establishment, serving as cabinet chief to Prime Minister ⁠Paul-Henri ​Spaak in the late 1960s and European commissioner from 1977 to ​1985. He held a number of board positions at Belgian and foreign companies.