Egyptian police questioned and detained Italian pupil Giulio Regeni just before his abduction, torture and murder, Egyptian and Italian prosecutors have said.
But they say the inquest was dropped after reasoning he posed no threat.
It really is the first official Egyptian acknowledgement that the security services were monitoring Regeni, correspondents say.
His body, revealing signs of torture, was found dumped near Cairo on 3 February.
The 28-year-old Cambridge University student had been studying trade unions, a sensitive topic in Egypt, when he went missing in Cairo on 25 January.
No one has been detained over Regeni’s death, although in March Egyptian authorities claimed to have found a criminal gang accountable for his kidnapping and murder.
All the gang members were killed in a shoot out, they said. The claims are branded “implausible” by academics who’ve criticised the Egyptian authorities.
The statement said the prosecution service of Egypt was still investigating the gang’s links to the abduction of Regeni.
Egyptian and Italian prosecutors will also be trying to retrieve footage from CCTV cameras from a metro station Regeni is considered to have entered before being abducted.
Egypt had asked Italy to help and the process of recovering the deleted footage is high-priced, Egyptian officials said.
Authorities have since offered little advice on the progress of their investigation, and initially indicated Regeni was killed in a road mishap.
An Italian autopsy revealed that his body was covered with cuts and had numerous broken bones, suggesting he had been hit with “fists, batons and hammers”.
The parents of Regeni Paola and Claudio have joined calls for the Egyptian authorities to work more fully with the Italian government.
In April, the UK Foreign Office condemned “the brutal style of [Giulio Regeni’s] killing” and declared it was “disappointed by the limited progress made in the case”.