The first trial into Giulio's murder was suspended was halted, bitterly disappointing his family
A second trial of four members of the Egyptian security forces accused of murdering an Italian student in 2016 has opened in Rome.
The four Egyptians, who have denied the charges, will be tried in absentia.
Giulio Regeni, 28, was studying for a doctorate at Cambridge University when he went missing while on a research trip in Egypt.
Days later, his mutilated body was found in a ditch near Cairo. An autopsy later revealed he had been tortured.
The case strained relations between Italy and Egypt, with Rome repeatedly accusing Cairo of blocking attempts at securing justice for Mr Regeni's death.
The four security officials were first due to go on trial in absentia in October 2021, but that the trial was suspended due to concerns prosecutors had been unable to track them down to issue the charges.
In September, Italy's constitutional court ruled that the case could go ahead in the defendants' absence.
Mr Regeni's parents, Claudio and Paola, and his sister, Irene, attended the start of the trial on Tuesday.
Holding yellow roses, they unfurled a matching yellow banner outside the courthouse, which reads: "Truth for Giulio Regeni". They told Italian media that they had been waiting for this day for eight years.
Giulio Regeni was abducted on 25 January 2016 while carrying out research for his PhD at Cambridge University on Egypt's independent trade unions - a politically controversial topic in Egypt.
His body was discovered days later, on 3 February, in a ditch by a road connecting Cairo to Alexandria.
His mother told the Italian parliament in 2018 that her son's body was so disfigured that she was only able to identify him by the tip of his nose. Prosecutors said he sustained injuries that showed he was beaten with "kicks, fists, sticks and clubs", and that he died from a broken neck.
Italian and Egyptian prosecutors originally investigated the case together but reached opposing conclusions.
