Brother of al-Qaida’s top leader Ayman al-Zawahri arrested in Egypt

CAIRO, Egypt – Egyptian authorities have arrested the brother of al-Qaida 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 Egypt’s July 3 coup. He was allied with ousted President

Mohammed Morsi, an Islamist, whose supporters are now taking to the streets to protest the killings of its supporters in a security crackdown last week.

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 left 173 people dead on Friday, 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 coalitionsays 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 remained after barricading themselves inside overnight.