PESHAWAR, Aug 18: A son-in-law of Al Qaeda No 2 Dr Ayman Al-Zawahiri is believed to be the mastermind of the plot to blow up transatlantic flights and he met one or some of the plotters at a place close to the Pakistan-Afghan border, credible sources told Dawn. “The mastermind in the planes bombing plot is Zawahiri’s son-in-law,” said the sources who did not want to be named. “He is the guy being looked for,” they added. Osama bin Laden’s top lieutenant is known to have several sons-in-law. One of them was reported to have been killed in a...