Ahmed Tharwat, the son-in-law of Muslim Brotherhood Deputy Supreme Guide Khairat El-Shater, was arrested by Egyptian security forces upon his arrival from Qatar, state media reported on Saturday.
Tharwat, a member of the Brotherhood, had been “kidnapped” and missing for the past three days, said Brotherhood spokesperson Wafaa Al-Banna.
State media added that Egypt’s intelligence services had tracked phone calls between Tharwat and the Muslim Brotherhood abroad.
According to Al-Banna, Brotherhood detainees are usually detained by intelligence officers and nothing is known about their whereabouts. They then emerge at a police station “after accusations are forged”, she claimed.
Since the 3 July 2013 ousting of former President Mohamed Morsi, authorities have cracked down on the Brotherhood. The interim authorities designated the group as a terrorist organisation on 25 December 2013. All top leaders have been arrested or are on the run.
El-Shater, the Brotherhood’s second-in-command, was arrested on 5 July, two days after Morsi’s ouster.
He is charged in several cases, including forming an operations room to spread chaos in Egypt.
El-Shater’s son was also arrested by interim authorities on 28 August. He is facing charges of funding a terrorist organisation and inciting violence.