A bomb blast hit a Cairo bus on Thursday, injuring at least four people.<br/> <br />Egypt's interior ministry says the homemade device was placed on a traffic island.<br/> <br />A second device found nearby was dismantled.<br/> <br />The blast is the latest in a series of attacks across Egypt over the last few days.<br/> <br />A car bomb killed 16 in Egypt's Nile Delta on Wednesday.<br/> <br />And a deadly attack on a police compound in the city of Mansoura the day before injured some 140 people.<br/> <br />Bomb attacks and shootings have become an almost daily occurrence in Egypt's Sinai peninsula since July.<br/> <br />That's when the army toppled Islamist President Mohamed Mursi following mass protests against his rule.<br/> <br />The recent attacks raise fears of intensifying violence in the run-up to a constitutional referendum in January.
