At least 1,300 detained in Egypt's anti-Sisi protests
Egyptian security forces on Tuesday night arrested Hazem Hosny, a prominent professor of political science at Cairo University, at his home in Giza.
Hosny formerly acted as an advisor to Sami Annan, a former general who was detained by Egypt's military in 2018 just days after announcing his intention to run against Sisi in that year's presidential elections.
The family of fellow political scientist Hassan Nafaa said they also feared his arrest after losing contact with the outspoken academic hours before Hosny's detention.
Both professors have spoken out in support of the protests on social media in recent days.
The defense committee for Hosny on Wednesday urged the professor's release, citing his poor health.
Hosny is among several prominent opposition figures detained in recent days as Sisi's regime moves to crackdown on dissent amid calls for a "million-man" protest on Friday.
At least 16 members of the opposition Independence Party were arrested on Tuesday.
The party had earlier issued a public call for Egyptians to participate in the protests, which erupted on Friday last week in the capital Cairo and other cities.
Thousands of demonstrators reportedly took the streets on Friday and Saturday as part of an unprecedented wave of dissent - more easily expressed online - sparked by allegations of corruption in Sisi's government and military.
Videos published by former government contractor Mohamed Ali went viral earlier this month.
The self-exiled former regime insider alleges that Sisi and the military appropriated millions of dollors of public funds to build several lavish villas and a colossal presidential palace.
As much as 60 percent of the Egyptian population lives in poverty.
Security forces have also detained the deputy heads of both the Communist and Dignity parties.
Some 1,300 people have been detained so far since the protests began, according to the Egyptian Center for Economic and Social Rights.
While Cairo has launched an internet blackout targeting social media sites, limiting the information available to reporters outside of the country, the spread of reported arrests in provinces across Egypt indicates that the protests have also taken place outside of major cities.
More than 300 detainees have appeared so far before the courts, all of them sentenced to 15 days in prison each to be interrogated regarding their participation in demonstrations.
Among those charged on Tuesday was award-winning human rights lawyer Mahinour El-Massry, who was arrested on Sunday after attending an investigation of several of those arrested during the demonstrations.
Others have found themselves levied with additional charges, including membership in a terrorist group - likely a reference to the outlawed Muslim Brotherhood, who Egyptian state media has accused of influencing protesters.
Judicial sources told The New Arab's Arabic service that more than 350 detainees had been released without charge in recent days, but hundreds more were yet to appear before the courts.
Sisi has ordered prosecutors from other departments to work in the Supreme State Security Prosecution court as his government attempts to deal with the protests, signalling the prospect of a wider arrest campaign, sources said.
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