CAIRO Egyptian authorities have arrested the brother of al Qaeda chief Ayman al-Zawahri, a security official said Saturday.
He said Mohammed al-Zawahri, leader of the ultraconservative Jihadi Salafist group, was detained at a checkpoint in Giza, the city across the Nile from Cairo.
Mohammed al-Zawahri's group espouses a hard-line ideology but was not clandestine prior to. He was allied with ousted President Mohammed Morsi, an Islamist, whose supporters to protest the killings of its supporters in .
The official declined to give further details. He spoke anonymously as he was not authorized to talk to the press.
Authorities said earlier that al-Zawahri had commanded insurgents in Sinai Peninsula.
Street fighting in Cairo and other clashes across the country, authorities say.
An anti-military coalition led by Morsi's Muslim Brotherhood has called for a week of protests, further escalating unrest in the country. The coalition says that they won't back down until it topples the government installed by the military.
Clashes continued Saturday morning near a downtown Cairo mosque, where hundreds of Morsi's supporters.