Egypt is denying reports that an Italian doctoral student doing research in Cairo was arrested shortly before his death, saying that an investigation into Giulio Regeni's killing continues with full Italian collaboration.

An Interior Ministry statement issued Monday says the outcome of the ongoing probe will be made public once there is "solid" information. The ministry oversees the police and security agencies.

Regeni was living in Cairo to research Egyptian labor movements for his doctorate from Britain's Cambridge University. His body was found on Feb. 3, nine days after he disappeared.

Italian state TV said Friday that Italian investigators have spoken to a witness who told them that two alleged plainclothes policemen stopped Regeni and escorted him away as he walked from his Cairo apartment to the subway station.