By Nathan Morley
Four years after his death, the killer – or killers – of student Mr. Regeni still remain unknown.
He went missing in Cairo on 25 January 2016 – his disfigured body was found nine days later in a ditch by the side of a highway.
A post-mortem examination found he had endured torture before his death from a broken neck.
His murder caused a diplomatic spat between Cairo and Rome, with Italian prosecutors accusing Egyptian officials of misleading the investigation.
Now, Italian prosecutors are reported to be planning to put up to five members of the Egyptian security forces on trial in Italy in absentia.
 They suspect Regeni was killed by Egyptian security forces because of his research into independent trade unions, a subject fraught with controversy in Egypt.
For their part, the Egyptians deny the accusations and say the student may have been the victim of a mugging.
On hearing of the suspension of the investigation, Regeni’s family called on the Italian government to recall its ambassador to Egypt.