Luca Attanasio, Italy's former ambassador to the DRC, was among three people killed on February 22, 2021, when a UN convoy was ambushed in the country's troubled east.
The other fatalities were driver Mustapha Milambo and Italian police officer Vittorio Iacovacci.
A military tribunal examining the murders opened in Kinshasa in October.
On Thursday, military prosecutor Bamusamba Kabamba, told the court that the victims had been kidnapped" and "dragged deep into the forest before being killed".
He requested the death penalty for all six men accused in the case. Five of the men are being held in prison in Kinshasa, while the other is on the run.
During previous hearings, the prosecution cast the defendants as criminals who had initially intended to kidnap the ambassador and demand a $1 million ransom.
The defendants, who were arrested in January 2022, denied any wrongdoing and said their initial confessions were extracted through torture.
The tribunal is due to hold another hearing on Saturday, where the defense is expected to wrap up its case.
A final judgement is expected at an undefined later date.
Much of eastern DRC is prey to armed groups, many of which are a legacy of regional wars that flared during the late 1990s and early 2000s. Militia attacks against civilians in the volatile region are common.
DRC Seeks Noose for Ambo Killers
Prosecutors in the trial of six people accused of murdering Italy's DRC ambassador in 2021 requested the death penalty Wednesday during an indictment hearing in the capital Kinshasa.
KINSHASA —
