In this February 12, 2016, file photo, the family of Giulio Regeni follows his coffin during the funeral service in Fiumicello, Northern Italy. Egyptian prosecutors have ordered the detention for 15 days of a lawyer who assisted the family of an Italian graduate student killed under suspicious circumstances during a police crackdown in Cairo, accusing him of disseminating false news. Ibrahim Metwally was arrested at Cairo International Airport while traveling to Geneva for a U.N. meeting on enforced disappearances. (File picture: AP)

Egypt on Wednesday ordered the detention of a prominent rights lawyer, who investigated the murder case of an Italian researcher in Cairo, for 15 days for questioning on charges of setting up an illegal group.

Ibrahim Metwally is the co-founder of the Association of the Families of the Disappeared in Egypt. He is being investigated at the state security prosecution for "illegally" establishing the association as well as "disseminating false information."

Metwally was arrested at Cairo airport on Sunday while he was on his way to Geneva to attend a United Nations meeting on enforced disappearances.

He is known for investigating the abduction and murder of Giulio Regeni, the Italian university researcher who was found dead on the outskirts of Cairo in 2016, with evident signs of torture. Metwally represented the Regeni family in the case which led to diplomatic tension between Cairo and Rome.

His arrest comes as a new Italian ambassador is expected to return to Egypt this month, after Italy decided to end the 16-month diplomatic freeze.

Metwally's detention also comes amid an uproar in Egypt against a report by Human Rights Watch, which stated that widespread arbitrary arrests, enforced disappearances and torture have increased since 2014. The foreign and interior ministries as well as lawmakers have repeatedly dismissed the report as "fabricated".

- DPA