A suicide bomber has slammed his explosive-laden car into a busy cafe in Iraq's capital, part of a day of violence across the country that killed 45 people, authorities said.

Egyptian anti-riot police fired tear gas at hundreds of supporters of the country's ousted Islamist president, besieging them inside a prestigious Muslim institution after stone-hurling protesters cut off a main road.

Amid all the bloodshed, confusion and deadlock of Syria's civil war, one fact is emerging after 2 1/2 years - no conflict ever has been covered this way.