The interior ministry of Democratic Republic of Congo has blamed the killing of Luca Attanasio on members of the Democratic Forces for the Liberation of Rwanda (FDLR).
FDLR is a Rwanda Hutu rebel group that has plagued the region for more than a quarter of a century.
Luca Attanasio died of his wounds on Monday after a World Food Programme convoy came under fire near the eastern city of Goma while he was on a field trip.
However, the Rwandan Hutu rebels denied the allegations that they were behind the killing of the Italian Ambassador to the Democratic Republic of Congo.
The group denied being involved in the attack and called on Kinshasa and UN peacekeeping force MONUSCO to shed light on the killings instead of resorting to hasty accusations.
The rebel group accused the armies of the DRC and Rwanda.
Some of the group’s founders were involved in the 19o4 Rwandan genocide during which the Hutu majority slaughtered 800, 000 people.