In both those instances, the bombs were made by al-Qaida's master bomb maker in Yemen, Ibrahim Hassan al-Asiri. Officials believe this latest bomb was the handiwork of al-Asiri or one of his students.
In the meantime, Americans traveled Tuesday with little apparent concern.
"We were nervous — for a minute," said Nan Gartner, a retiree on her way to Italy from New York's John F. Kennedy Airport. "But then we thought, we aren't going anywhere near Yemen, so we're OK."
Associated Press writers Kimberly Dozier, Ted Bridis, Bob Burns, Bradley Klapper and Alan Fram in Washington, Ahmed Al-Haj in Sanaa, Yemen, Verena Dobnik in New York, Paisley Dodds in London, Matthew Lee in New Delhi and Slobodan Lekic in Brussels contributed to this report.
Contact the Washington investigative team at DCinvestigations(at)ap.org