today on inside politics, two major breaking stories out of the middle east. another massive blast at a refugee camp in gaza. we re getting new video showing the catastrophic damage as people dig through the rubble searching for bodies. we do not know yet who is responsible. is it the same camp that israeli forces struck yesterday. we re also covering a huge breakthrough, civilians are now leaving gaza for the fist time since a mass attacked israel. hundreds are waiting to move through the crucial rafah border crossing. u.s. officials believe more than 5,000 could ultimately be allowed to leave as part of a deal brokered by qatar. we have cnn reporters across the region covering the latest on all of these stories. melissa bell is in cairo. we start jeremy diamond near the gaza border. what do we know about this second blast? reporter: for the second day in a row, a massive blast appears to have hit the refugee camp inside gaza. this is the largest refugee camp in gaza his