Pro-Russian separatists look through the debris of an IL-76 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
June 14 marks the deadliest day of the undeclared war between Ukraine and pro-Russian separatists in the country's eastern regions after Kremlin-backed insurgents shot down a Ukrainian military cargo plane carrying 49 servicemen. All were killed.