After a trial lasting nearly five years, 51 people found guilty of the killing of United Nations investigators Michael Sharp and Zaida Catalan were sentenced to death on Saturday by a military court in Congo. 

Many of the sentences were handed out in absentia, as suspects were either never arrested or escaped from custody.

Congo has observed a moratorium on the death penalty since 2003, so those sentenced to death will likely serve life sentences.

When were the UN officials assassinated?

Sharp and Catalan were assassinated on March 12, 2017, in Congo's central Kasai region. They were on a field visit with representatives of Kamwina Nsapu, a militia active in Kasai whose customary chief Jean-Pierre Mponde was killed by Congolese army troops in August 2016.

Sharp was from the United States and Catalan from Sweden.

The two UN experts were investigating violence in Kasai on behalf of the UN Security Council.

The Congolese government blames the killings on members of the Kamwina Nsapu militia.

The government initially denied any state agents were involved, but later a number of officials were arrested.

Colonel Jean de Dieu Mambweni was sentenced to 10 years on Saturday for failing to assist a person in danger. A local immigration official, who had met with Sharp and Catalan the day before their mission, was given a death sentence.

The military court acquitted journalist Trudon Raphael Kapuku and police officer Honore Tshimbamba, who were arrested separately in 2018 and have spent 4 years in prison.

Investigations 'failed to uncover the full truth'

Human Rights Watch senior researcher on Congo Thomas Fessy said "the investigation and this trial have failed to uncover the full truth about what happened."

"Congolese authorities, with UN support, should now investigate the critical role that senior officials may have played in the murders," Fessy said in a tweet.

Swedish Minister of Foreign Affairs Ann Linde said on Twitter that investigations must continue.

"Crucial that investigation concerning others involved continues to further uncover truth and bring justice," Linde said. "We encourage authorities to fully cooperate with the U.N. mechanism."

sdi/sms (AP, AFP, Reuters)