The lawyer investigating the case of murdered Cambridge student Giulio Regeni has said that he was abducted and tortured by Egyptian security services while travelling to Cairo airport.

Ibrahim Metwaly Hegazy was reported missing on the 12th September. He had been due to fly to Geneva to speak to a UN working group about the Regeni case, but was instead found at the office of the Egyptian state security prosecutor, being interrogated on charges of “communicating with foreign entities to harm state security.”

Mr Metwaly then appeared before prosecutors, charged with “managing an illegal group, spreading false news … [and] cooperating with foreign organisations,” a charge that can carry a prison sentence of up to five years.

At a hearing yesterday to extend his detainment for a further 15 days, Mr Metwaly told the Egyptian Commission for Rights and Freedoms (ECRF) – the group represents the Regeni family in Egypt, and with which Metwaly is closely involved – that he had been tortured and kept in solitary confinement while in prison.

Speaking to The Times, ECRF’s executive director Mohamed Lotfy said: “He told our lawyers that he was subjected to torture when he was in state security during his disappearance. They stripped off all his clothes and electrocuted him.”

“He is being held in solitary confinement in a dark room without electricity and with water on the floor that is full of garbage.”

Mr Lofty also said that after yesterday’s hearing, the offices of ECRF were raided by Egyptian security forces. He added that the authorities had accused the commission of acting politically and in breach of its founding contract. He expects another attempt to close down ECRF next week.

As well as being a senior figure in ECRF, Mr Metwaly is a co-founder of the Association of the Families of the Disappeared, a group for relatives of those who have been forcibly disappeared. Metwaly’s own son disappeared in 2013 while working for the the Egyptian Commission for Rights and Freedoms, a Cairo-based NGO.