An Egyptian security source told ANSA news agency on Friday that: "Two people have been arrested [and are] suspected of the murder of Italian student Giulio Regeni."
The source ruled out the possibility that the murder had "political or terrorist links", adding that it was a "criminal act".
Giulio Regeni, a 28-year-old Cambridge University PhD candidate who had been researching labour rights in Egypt, went missing on January 25, the fifth anniversary of the popular uprising that toppled longtime autocrat Hosni Mubarak.
His body was found in a ditch on the side of a desert road on Wednesday.
An autopsy on the body has revealed that the doctoral student suffered "inhuman, animal-like" violence, Italy's interior minister said on Sunday as he pressed Egypt's president to fully cooperate with the criminal investigation.
A second post-mortem exam, following that one carried out by authorities in Egypt, was performed late on Saturday in Rome after the body was flown to Italy, concluded that Regeni died after a cervical vertebra was broken, said Alessandra Ballerini, a human rights lawyer appointed by the young man's family to follow developments in the case.
|Mourners held a vigil for Regeni in Cairo on Saturday [Getty]|
News of the slaying and suggested evidence of torture has raised diplomatic tensions. An Italian government delegation cut short a visit to Cairo and Italy summoned the Egyptian ambassador in Rome, calling for a full investigation with participation by Italian experts.
Regeni's disappearance came at a time when Egyptian officials and media have often depicted foreigners as plotting against Egypt - and particularly as seeking to foment unrest surrounding the January 25 anniversary.
The Italian media has largely blamed the Egyptian security forces.
Regeni had been in Egypt since September conducting research on workers and labour rights - a sensitive topic, since disgruntled workers were among the forces of the 2011 anti-Mubarak uprising - and authorities still worry about worker discontent.
Italian newspaper Il Manifesto, at which Regeni submitted articles, has said the 28-year-old "feared for his safety" and had asked to publish his last article under a pseudonym.
The left-leaning newspaper on Friday published Regeni's final article for their paper, headlined In Egypt, second life for independent trade unions.
Egyptian media, meanwhile, have accused "hidden hands" of plotting Regeni's murder to damage Egyptian-Italian relations.
The term is usually used to refer to members of the now-banned Muslim Brotherhood, which has been the target of a ferocious crackdown since the 2013 military coup against Islamist President Mohammad Morsi.
"The timing of the murder proves that there are hidden hands keen on destroying Egypt's economy and severing the bonds between Cairo and Rome," wrote journalist Mahmoud Abdel Radi in a local newspaper.
"Hands that have orchestrated the murder of a foreigner while a minister from his country was visiting Cairo," Abdel Radi added.
In response to media allegations that Regeni was a spy, Italy's minister of interior spoke out, saying: "We adamantly reject the lies that have been published by some irresponsible media outlets that [Regeni] was connected to the Italian intelligence service."
Controversial pro-government TV anchor Ahmad Moussa blamed "fifth columnists" - a thinly veiled reference to Egypt's Islamists - for the accusation that the police were involved in the killing.
"The fifth column - you know who I'm talking about - are carrying out a relentless campaign against the police to turn the people against them, which many have bought into," Moussa said.
"People are killed all the time in Italy; tourists, Arabs, Egyptians and foreigners, it's normal," he added.
"Maybe there are a thousand bad cops out of a million. Do they tarnish the reputation of the vast majority? Of course not, they are tarnishing themselves and will be punished," Moussa claimed.
Rights groups frequently accuse Egyptian police and members of the intelligence services of abusing and torturing detainees.
As a further example of Egypt's media landscape, another talk show host, Tamer Amin, even claimed it was possible that Regeni's murder could have been a result of him being homosexual, adding that he did not understand why the case was receiving so much attention.