Armenia and Azerbaijan accused one another on Tuesday of firing directly into each other's territory and rejected pressure to hold peace talks as their conflict over the enclave of Nagorno-Karabakh threatened to spill over into all-out war.
Both reported firing from the other side across their shared border, well to the west of the breakaway Nagorno-Karabakh region over which fierce fighting broke out between Azeri and ethnic Armenian forces on Sunday.
The incidents signalled a further escalation of the conflict despite urgent appeals from Russia, the United States and others to halt it.
Azerbaijan's President Ilham Aliyev, speaking to Russian state TV, flatly ruled out any possibility of talks.
Armenian Prime Minister Nikol Pashinyan told the same channel that talks could not take place while fighting continued.
Further fuelling tensions between the two former Soviet republics, Armenia said an F-16 fighter jet belonging to Azerbaijan's close ally Turkey had shot down one of its warplanes over Armenian airspace, killing the pilot.
It provided no evidence of the incident. Turkey and Azerbaijan called the claim "absolutely untrue".
Dozens of people have been reported killed and hundreds wounded since clashes between Azerbaijan and its ethnic Armenian mountain enclave of Nagorno-Karabakh broke out on Sunday.
Nagorno-Karabakh is a breakaway region that is inside Azerbaijan but is run by ethnic Armenians and is supported by Armenia. It broke away from Azerbaijan in a war in the 1990s, but is not recognised by any country as an independent republic.
A descent into all-out war could drag in regional powers Russia and Turkey. Moscow has a defence alliance with Armenia, which is the enclave's lifeline to the outside world, while Ankara backs its own ethnic Turkic kin in Azerbaijan./Reuters