Prosecutors in Egypt have charged six journalists working for the independent fact-checking platform Matsda2sh with belonging to the outlawed Muslim Brotherhood, according to their lawyer.

President Abdul Fattah al-Sisi has overseen what human rights groups say is an unprecedented crackdown on dissent since he led the military's overthrow of his predecessor, Muslim Brotherhood leader Mohammed Morsi, in 2013.

Tens of thousands of people have been detained, mainly Muslim Brotherhood officials and supporters but also leading secular and liberal activists, media workers and academics.

Matsda2sh, whose name means "Do Not Believe" in Arabic, was founded in 2018 to "resist the flow of false or misleading news", according to its website.

It regularly fact-checks statements made by Egyptian officials and carries out investigative reporting in Egypt and other Arab countries.