throw off someone who you know is listening on your communications. >> reporter: isis in the sinai peninsula has shown bomb-making signals before and if isis is responsible for this, it would mark a significant step in their capabilities to launch further attacks. >> at this point, we don't have enough information to make our own determination about what exactly occurred but we do have enough information at this point to not rule out the possibility of terrorism. >> reporter: there is no indication so far that passengers or crew aboard the flight had any connection to terror groups so investigators are looking at a possible inside job. a not so sophisticated bomb planted by an employee at egypt's sharm el-sheikh airport. >> we're really kind of limited to either a timing situation or a barometric pressure switch bringing down an aircraft. >> reporter: tonight, egypt and