General prosecutor ordered five of Al-Jazeera staff members Tuesday to be detained 15 days pending investigations, judicial sources said.
Sources said charges included belonging to a terrorist group, providing it with information and recordings, publishing false news on the country's conditions that could "harm the national benefit and disrupt the general peace".
Staff members and journalists of Qatar's Al Jazeera Channel were arrested Monday following Interior Ministry accusations of illegally broadcasting from a hotel suite.
The arrest came upon the cabinet's decision Wednesday designating the Muslim Brotherhood as a terrorist group.
Al Jazeera's Cairo offices have been closed down since 3 July, after being raided by security forces in the immediate aftermath of the ouster of President Mohamed Morsi, who hails from the Brotherhood.
The only Al Jazeera-affiliated channel to have been banned with a court order is Al Jazeera Mubashir Misr, while all other sub-channels have been closed without one.
Launched weeks after the ouster of former president Hosni Mubarak and widely perceived as the voice of the Brotherhood, the channel operated for over two years without accreditation.
The channel network, which now broadcasts from Qatar and can still be viewed in Egypt, was accused by authorities and local media of biased coverage in favour of Morsi's Brotherhood.