Armenia has already retaliated against Azerbaijan for the downing of a military helicopter last month, Armenia's defense minister has said, without saying what the retaliation amounted to.
The Mi-24 helicopter was shot down November 12 near the line of contact between Armenian and Azerbaijani forces in the disputed territory of Nagorno Karabakh; Armenia says it was on a training flight, Azerbaijan says it had crossed the line of contact and was planning an attack.
Armenia immediately promised to retaliate, but it wasn't clear how. And on December 23, Armenian Defense Minister Seyran Ohanian said it has already happened: "A disproportionate response to the Azerbaijani side has been given, part of the information about the operation was given to the public. However, it wasn't appropriate to release all of the information."
The most significant military incident since the shootdown that was partially reported was a heavy exchange of fire, including relatively rare mortar attacks, in early December. The de facto Nagorno Karabakh government claimed that five to seven Azerbaijani soldiers were killed, though that wasn't independently confirmed. Still, even that would seem to not meet the standard of retaliation that Armenia had been promising.
The result of the retaliation would be "massive, painful losses for the enemy, to disturb Azerbaijani society, to sow serious doubts in the ruling regime, to strike a blow to the reputation of the Aliyev clan," said David Djamalyan, an adviser to Armenia's MoD, in an interview earlier this month.