Azerbaijan's defence ministry says its forces have shot down an Armenian military helicopter violating its airspace.Three crew members were killed in the incident, according to local reports.The helicopter was flying in the disputed territory of Nagorno Karabakh, an enclave in western Azerbaijan controlled by ethnic Armenians.
BBC News*, 2014-11-12
It's still about that old Nagorno-Karabakh territorial conflict.
related: 2011-08: Territorial disputes
*: I'm not sure why they claim the war began in 1988.
The USSR was still in place at that time.