Luca Attanasio, 43, and Vittorio Iacovacci, 30, were shot dead after being kidnapped while travelling in a United Nations’ World Food Programme convoy to visit a school feeding project on Monday.

WFP driver Mustapha Milambo was also killed and was buried in DR Congo on Tuesday.

The funeral, attended by Prime Minister Mario Draghi and other ministers, was held in the Basilica of St Mary of the Angels and Martyrs in Rome, a church used for religious services for national leaders and cultural figures.

The caskets, draped in the Italian flag, were given a military salute as they were removed from hearses.

A soldier commanded “Honour to the Fallen” and a military band played a sombre march as they were carried into the church.

“These brothers decided to commit themselves to helping others even if it meant sacrificing their lives,” Cardinal Angelo De Donatis said in his funeral homily.

De Donatis, who is Pope Francis’s vicar for Rome diocese, said the deaths should prompt everyone to “hear the cry of the people of Congo, cruelly devastated by violence as it sees its sons and daughters die every day”.

Attanasio leaves behind a wife and three young daughters, and Iacovacci was engaged.

A judicial source in Rome said preliminary autopsy results showed that both were hit twice by crossfire in an apparent kidnapping attempt and not executed.

Italy has formally asked the UN for an immediate inquiry into the attack, amid questions such as whether the security provisions were sufficient for the mission, organised in a very dangerous area of the war-torn country.

Italian investigators have flown into Congo to liaise with police there.

When they return home, Italian prosecutors are expected to open a full investigation.

Local militias have been blamed for the attack by Congo’s authorities.

Congo’s President Felix Tshisekedi has said he wants to end decades of unrest in the east of the country, which is rich in precious metals and devastated by local infighting, but killings have more than doubled in the past year, according to the UN.