Egypt refuses to accuse police officers suspected by Italy of involvement in the grisly murder of an Italian student because of a lack of evidence, authorities said.
According to Italian media, Italian prosecutors could open a formal investigation into several Egyptian secret service agents.
Giulio Regeni, a 28-year-old doctoral researcher at Britain's Cambridge University, disappeared in Cairo in 2015.
Regeni, a PhD student, went missing in the Egyptian capital on January 25th, 2015. His body was found days later by a roadside, bearing torture marks
An Italian autopsy showed that Regeni's body was covered with cuts and his bones were broken, indicating he had been hit with "fists, batons and hammers".
A letter "X" was carved on his forehead and hand, according to the report cited by Italian media.
The a case has strained traditionally close relations between Cairo and Rome, which accused Egypt of insufficient cooperation in the probe.
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Egypt has always strongly denied suggestions that its security services were involved in the death of Regeni, who was researching trade unions in Egypt, a politically sensitive topic in the country.
"Charges should be based on evidence and not suspicions," Egypt's State Information Service said in a statement released late on Sunday.
Egyptian and Italian public prosecutors met in Cairo on Wednesday to discuss the investigations into Regeni's case, it said, quoting a judicial source.
The Italian prosecutors asked their Egyptian counterparts "to approve the inclusion of a number of Egyptian policemen on its register of suspects in Italy", it added.
The policemen are suspected by Italian prosecutors of gathering information about Regeni, according to the source.
Frustrated at the slow pace of the probe, Italy withdrew its ambassador to Egypt in April 2016, but sent a new envoy to Cairo the following year.
Egyptian authorities initially suggested Regeni died in a traffic accident, but later said he was killed by a criminal gang that was subsequently wiped out in a shootout with police.
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