The Gaza Strip's ruling Hamas group has replaced hundreds of striking teachers with its own supporters in a purge of the area's education system. The move has deepened Hamas' control of Gaza. But it also has disrupted the start of the school year. Many students have skipped class this week amid the uncertainty. Hamas violently seized control of Gaza last year, and the local teachers' union has been one of the few remaining strongholds of the rival Fatah movement. The union declared a strike this week to protest what it says is Hamas attempts to install supporters into key educational positions. The Hamas government responded by sacking hundreds of teachers and installing its supporters in their places.