CAIRO — Egypt’s capital descended into chaos Friday as vigilantes at neighborhood checkpoints battled Muslim Brotherhood-led protesters denouncing the ouster of President Mohammed Morsi and a deadly crackdown. The fiercest street clashes Cairo has seen in more than two years of turmoil left at least 82 people dead, including 10 policemen.
The sight of residents firing at one another marked a dark turn in the conflict, as civilians armed with pistols and assault rifles clashed with protesters taking part in what the Muslim Brotherhood called a ‘‘Day of Rage,’’ ignited by anger at security forces for clearing two sit-in demonstrations Wednesday in clashes that killed more than 600 people.
Military helicopters circled overhead as residents furious with the Brotherhood protests pelted them with rocks and glass bottles. Full story for BostonGlobe.com subscribers.