Azerbaijan - Nov 12
An Armenian Mi-24 helicopter was shot down by Azerbaijani force in the disputed territory of Nagorno Karabakh, an enclave controlled by ethnic Armenians. Azerbaijan's defense ministry claim the Armenian helicopter violating it airspace. This regional conflict date back to Soviet era when Armenian secessionists fight against Soviet controlled Azerbajian army, and was settledn in a ceasefire in 1994. However,tension has risen again recently. Source: BBC