An Armenian soldier of the self-proclaimed republic of Nagorno-Karabagh walks in a trench at the frontline on the border with Azerbaijan near the town of Martakert on July 11, 2012. AFP  
An Armenian soldier of the self-proclaimed republic of Nagorno-Karabagh walks in a trench at the frontline on the border with Azerbaijan near the town of Martakert on July 11, 2012. AFP  

Four killed as border clashes reignite Armenia-Azerbaijan conflict