UNITED NATIONS, Feb. 23-- The Italian ambassador to the Democratic Republic of the Congo (DRC), killed en route to visit a school feeding program, was ambushed on a road declared safe for travel, UN officials said on Monday. The attackers killed two others, along with ambassador Luca Attanasio, the World Food Programme (WFP) said. They were identified as an Italian security guard and a local WFP driver. Several others were injured. "They were travelling from Goma to visit a WFP school feeding program in Rutshuru," said Stephane Dujarric, the chief spokesman for UN Secretary-General Antonio Guterres. "There are a number of rebel groups operating in the area, so ... I don't want to point in one direction or another." The peacekeepers in UN mission known as MONUSCO have been fully mobilized and will be working with their Congolese counterpart in the investigation, said Dujarric, who added he had sparse details of the attack. Undersecretary-General Jean-Pierre Lacroix, head of UN peacekeeping operations, also said he lacked details. But he told reporters in a previously-scheduled briefing the incident occurred about 25 km from Goma and involved "a WFP convoy of two vehicles on a road that was determined safe for a transit without escort." "Normally these determinations are made by our colleagues who are in charge of security in the country" involved, he said. "The victims were brought to MONUSCO hospital in Goma. We have a level 3 hospital there. A level 3 is quite a significant facility with a capacity to provide (the) most sophisticated health treatment." "There is a presence, actually a significant presence of MONUSCO in Goma so certainly peacekeepers were no further than 25 km" from the ambush site, Lacroix said.