Pro-Russian militants look through the debris of an IL-76 Ukrainian military transporter which was taken down by pro-Russian rebels early on June 14, on the outskirts of Lugansk June 14, 2014. Ukraine's new Western-backed President Petro Poroshenko vowed Saturday to deliver an 'adequate response' to pro-Russian rebels who downed a military transport plane, killing 49 troops. AFP PHOTO / DANIEL MIHAILESCU        (Photo credit should read DANIEL MIHAILESCU/AFP/Getty Images)