These are the preliminary results of the autopsy, however further clinical tests are required to ascertain which blow was fatal for the 21-year-old, who died in Colleferro, near Rome, in the early hours of Sunday.

Four men have been charged with involuntary manslaughter in relation to Duarte’s death, but the results of further investigations could lead to the more serious charge of voluntary manslaughter, according to Italian daily La Repubblica.

Emanuele Cenciarelli, a key witness of the savage beating which resulted in the death of his friend was quoted by Corriere della Sera as saying: “They were jumping on him when he was lying helpless on the ground.”

Three of the four arrested, currently detained in Rome’s Rebibbia prison, have been named as brothers and mixed martial arts practitioners Gabriele and Marco Bianchi, aged 26 and 24, and Mario Pincarelli, 22.

The fourth, Francesco Belleggia, 23, has been released from Rebibbia and placed under house arrest after an investigating judge recognised his “more nuanced role” in the attack, Corriere della Sera reported.

Magistrates on Wednesday reconstructed a scene of “unmotivated and unprecedented” violence against a young man who “had nothing to do with” the fight, which was triggered by a trivial matter.

On Wednesday night, hundreds of people attended a candle-lit procession, demanding “Justice for Willy” in Duarte’s hometown of Paliano, near Colleferro.

Duarte’s funeral is likely to take place at the sports field in Palliano on Saturday, September 12, according to local media.