CAIRO - Egyptian security forces stormed a Cairo mosque today after a heavy exchange of gunfire with armed men shooting down from a minaret, rounding up hundreds of supporters of the country's ousted president who had sought refuge there overnight after violent clashes killed 173 people.
The raid on the al-Fath mosque on Ramses Square was prompted by fears that deposed President Mohammed Morsi's group, the Muslim Brotherhood, again planned to set up a sit-in, security officials said, similar to those that were broken up Wednesday in assaults that killed hundreds of people.
The arrest of the brother of al-Qaida chief Ayman al-Zawahri came in connection to the raid on the mosque. Officials said that he planned to bring in armed groups to provide support to those holed up inside the mosque.
Mohammed al-Zawahri, a Morsi ally, is the leader of the ultraconservative Jihadi Salafist group which espouses al-Qaida's hardline ideology. He was detained at a checkpoint in Giza, the city across the Nile from Cairo, the official said.
The official spoke on condition of anonymity as he wasn't authorized to brief journalists about the arrest.
The Egyptian government meanwhile announced it had begun deliberations on whether to ban the Brotherhood, a long-outlawed organization that swept to power in the country's first democratic elections a year ago.
Such a ban - which authorities say is rooted in the group's use of violence - would be a repeat to the historic and decades-long power struggle between the state and the Brotherhood.
The assault on the al-Fath Mosque began Friday, as pro-Morsi protesters and armed men fled into the worship center to avoid angry vigilantes and arrest. They piled furniture in the mosque's entrance to block authorities and enraged anti-Morsi protesters from reaching them.
The mosque served as a field hospital and an open-air morgue as a Brotherhood-called day of protests descended into violence. By daybreak today, security forces and armored personnel carriers had surrounded the mosque and it appeared that military-led negotiations might defuse the standoff.