A Turkish fighter jet has been accused of shooting down of of Armenia warplanes and killed the pilot.
The F-16 fighter craft brought down an Armenian SU-25 warplane over Armenian territory, according to an Armenian defence ministry spokeswoman.
Shushan Stepanyan said the SU-25 was on a military assignment.
However, Turkey has since denied any involvement in the crash.
President Recep Tayyip Erdogan’s communications director said “the Armenian claim is false”.
He called it a “cheap propaganda stunt”, Bloomberg reports.
Armenia and Azerbaijan have clashed over the disputed Nagorno-Karabakh region on Russia’s southern border.
Turkey is backing Azerbaijan in the conflict, which has already left 100 people dead – including civilians – in three days of fighting.
It voted to become part of Armenia after the fall of the Soviet Union in the 1980s, resulting in a war and a frail ceasefire in 1994.
Azerbaijani President Ilham Aliyev told his security council on Sunday, September 27: “The settlement of the Nagorno-Karabakh issue is our historical mission.
“We must resolve this so that historical justice can be restored.
“We must do so to restore the territorial integrity of Azerbaijan.”
Russia, which has a military base in Armenia and a defence pact wth the country, has called for a ceasefire.