According to the Ministry of Defence in Baku, the helicopter was shot down after it fired on the Azerbaijani troops. The report did not mention any victims.
In Nagorno-Karabakh, the so-called self-defense forces of the Armenian separatists claim that the helicopter belonged to them, and it was shot down during the "training flight".
According to their statement, the helicopter posed no threat to the Azerbaijani troops. Three people were killed in the helicopter. So far, there are no independent reports on the event.
Fights on actual border between Nagorno-Karabakh and the rest of Azerbaijan happen regularly, despite the ceasefire proclaimed 20 years ago.
Nagorno-Karabakh is the autonomy within the internationally recognized borders of Azerbaijan. The majority of its population is ethnic Armenians. It declared independence after the 1988-1994 war in one-sided manner. After the war, Azerbaijan lost control of the region. Baku believes that it is occupied by Armenia. The self-proclaimed "independence" of Nagorno-Karabakh is not formally recognized by any state in the world, including Armenia. In fact, Yerevan provides this separatist region of Azerbaijan with full support.