A series of air strikes struck a military airport in Syria on Friday, killing 16 jehadists, including a top fighter from the al-Qaeda affiliated Al-Nusra Front, a monitor said. The Syrian Observatory for Human Rights said more than 60 air raids targeted the Abu Duhur military airport in Idlib province which Al-Nusra and allied Islamist fighters seized in September. Observatory director Rami Abdel Rahman said however that it was unclear if the strikes were carried out by the Syrian regime, Russian or US-led coalition aircraft.