>> reporter: officials have told cnn there was credible and specific intelligence that isis would try to attack aviation asse assets. >> there's an imperative to get isolation in place around raqqah. because our intelligence feeds tell us that there is a significant external operations attacks planning. >> reporter: al qaeda's official in yemen, aqap has been trying to carpet airliners destined for the u.s. hiding explosives in the batteries of electronic guys like laptops is one means. in february, 2016, a wakeup call when a laptop bomb, according to