The High State Security Prosecution on Friday ordered the detention of Mohamed Al-Qassas, deputy head of the Strong Egypt Party, for 15 days pending an investigation on charges of joining an outlawed group and spreading false news against the state. Al-Qassas, a prominent activist and a former Muslim Brotherhood member, was arrested a day earlier and his apartment was raided by security forces. According to his lawyer Mokhtar Mounir, Al-Qassas is accused of being a member of the banned Muslim Brotherhood which was designated a terrorist organisation by the government in 2013 for obstructing the law and the constitution and preventing state institutions and public authorities from performing their duties. The prosecution also accuses him of spreading false news about the economic and political situation in the country to disrupt public order. Al-Qassas, who left the group in 2011, faces charges along with 50 other defendants, according to Mounir. They include journalists and members of former presidential hopeful Sami Anan's campaign, well-known Twitter user Islam Al-Refaai (popularly known as Khorm), photojournalists Ahmed Al-Sakhawi and Ahmed Ali, as well as journalists Ahmed Abdel-Aziz and Hossam Al-Sweifi. On the day of his arrest, several members of Al-Qassas' family and party said his whereabouts were unknown. His first interrogation was on Friday. “The government and the interior minister bear full responsibility for the safety of Al-Qassas,” said a statement issued by the Strong Egypt Party a day before his interrogation. Several parties and activists issued a joint statement on Saturday condemning Al-Qassas' arrest, with the signatories, including various political parties and public figures and activists, referring to the incident as “illegal” by claiming that Al-Qassas was “kidnapped” and his personal belongings “illegally seized”. Strong Egypt Party president and former presidential candidate Abdel-Moneim Abul-Fotouh signed a statement last month along with a number of opposition figures in which they called for a halt to the presidential elections scheduled next month. Al-Qassas is being held in a high-security prison and is in solitary confinement, according to Mounir.