ROME — A court in Rome on Monday sentenced three Egyptian security officials convicted of aggravated kidnapping in the abduction of an Italian researcher in Cairo to 10 years in prison, while a fourth defendant was acquitted of murder.

The ruling marks the most significant judicial milestone yet in the decade-long quest for accountability over Giulio Regeni’s death. Rome’s chief prosecutor Francesco Lo Voi welcomed the outcome, saying the verdict was achieved despite what he described as a lack of “meaningful cooperation” from Egyptian authorities during the investigation.

“We are satisfied for having brought the case out of the quagmire into which it had risked sinking,” Lo Voi told reporters after the verdict.

Regeni, a 28-year-old Italian doctoral candidate at the University of Cambridge, disappeared in Cairo on Jan. 25, 2016, while conducting research on independent trade unions in Egypt. His body was found nine days later on the outskirts of the Egyptian capital bearing signs of extensive torture, according to Italian investigators.

Rome prosecutors had charged the four Egyptians: Tariq Sabir, Hisham Helmi, Athar Kamel Mohamed Ibrahim and Magdi Ibrahim Abdelal Sharif with aggravated kidnapping in connection with Regeni’s disappearance. Sharif had also faced charges related to Regeni’s injuries and death.

Helmi, Ibrahim and Sharif were sentenced Monday to 10 years in prison for charges related to Regeni’s abduction, but not for his death. Sabir was acquitted.

The case quickly became one of the most contentious issues in relations between Italy and Egypt. Italian prosecutors maintained that members of Egypt’s security services abducted, detained, tortured and killed Regeni, while Egyptian authorities repeatedly denied state involvement and disputed the findings of the Italian investigation.

The investigation was marked by years of disputes over evidence and judicial cooperation. Italian magistrates accused Egyptian authorities of withholding key information requested through international legal channels, an allegation Cairo rejected.

The proceedings faced repeated delays because the defendants remained in Egypt and never appeared before the Italian court.

Italy’s Constitutional Court ultimately cleared the way for the trial to proceed in absentia, allowing hearings to begin in Rome despite longstanding disputes over notification of the accused.

In June, prosecutors sought a life sentence for Sharif, whom they identified as the man who physically carried out the killing, and prison terms of 17 years and six months for Sabir, Helmi and Ibrahim.

For Regeni’s family, the case became a decade-long campaign for accountability. Their calls for “truth and justice” drew broad support across Italy, where yellow banners bearing Regeni’s name became symbols of solidarity and demands for answers over his death.

The ruling marks the most significant judicial milestone yet in a case that has repeatedly tested relations between Italy and Egypt and drawn international attention to human rights concerns in Egypt.