Egypt's state security prosecutor on Tuesday ordered a prominent activist under investigation for alleged "fake news" be detained for 15 days, his lawyer said.
Shadi Ghazali Harb, one of the youth leaders of the 2011 revolution, faces charges of "spreading fake news and joining a terrorist entity because of his posts on Facebook and Twitter", Abdul Rahman Haridi, who attended the interrogation, told AFP.
Harb, a surgeon, was one of the leaders of the Youth of the January 25 Revolution movement that emerged from the 2011 revolt that toppled longtime president Hosni Mubarak.
He was also a leader of the Al-Dustur party, from which he resigned in 2013.
"The prosecution did not specify what terrorist entity it is referring to, but it mentioned a number of other activists... including Amal Fathi," who was arrested Friday after publishing a video on Facebook criticising Egyptian institutions and sexual harassment.
Harb's interrogation was set to continue on Wednesday, his lawyer said.
Human rights organisations have accused President Abdel Fattah al-Sisi, re-elected in March with over 97% of the vote, of seeking to silence opponents.
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