MOSCOW — Armenia said Tuesday that Azerbaijan was employing longer range and more destructive types of artillery in fighting over the Nagorno-Karabakh region, now in its third day, and threatened to deploy heavier weapons of its own.
The Armenian Ministry of Defense also said that one of its jets had been shot down by a Turkish F-16. A spokeswoman said the Turkish plane had taken off in Azerbaijan, flown into Armenia, and shot down the Armenian military airplane.
Azerbaijan and Turkey denied this had happened. It was not immediately possible to confirm the Armenian claims about the planes or the Azerbaijani artillery barrage.
Fighting in Nagorno-Karabakh, an Armenian separatist enclave in Azerbaijan in a remote mountain area north of Turkey and Iran, began on Sunday and has killed at least dozens of people, threatening to pull in two major powers in the region, Russia and Turkey.
The conflict began after diplomats missed chances to tamp down simmering tensions in the region over the summer, in part because their governments were distracted by the pandemic, analysts have said.
The Armenian Defense Ministry said that Azerbaijan had begun firing from two powerful Soviet-made rocket artillery systems. In response, the Armenian military threatened it would roll out unspecified heavier weapons.
Also on Tuesday, the Armenian Foreign Ministry said a civilian had been killed inside Armenia in a strike by a Turkish-made armed drone. Armenia has a mutual defense treaty with Russia but has not asked that it be activated because of the fighting.
Armenia and Azerbaijan fought a war over Nagorno-Karabakh in the early 1990s, a conflict that ended in a stalemate with a cease-fire but no settlement.
Periodic border skirmishes have ensued since then. But the fighting now is distinct from clashes in recent years because of its scale and because Turkey is more openly backing Azerbaijan, a fellow Turkic-speaking country.
Turkish armed drones, similar to the United States’ Predator, are being used widely for the first time in the disputed region in the fighting that broke out this weekend, Richard Giragosian, director of the Regional Studies Center in Yerevan, said in telephone interview.
Their appearance, he said, was another indication that the Nagorno-Karabakh conflict, which simmered for decades without much interest from outside powers, has now become part of Russia’s broader competition for influence with Turkey.
The fighting has so far taken place in mostly unpopulated areas formerly inhabited by ethnic Azerbaijanis in a security buffer zone around the Nagorno-Karabakh region, which has declared itself an independent country but is not recognized as such by other nations. About 600,000 Azerbaijanis were driven from Nagorno-Karabakh in the war three decades ago.
But shelling has also hit populated areas in Nagorno-Karabakh. The military of the breakaway enclave said Tuesday that 84 of its soldiers had died in the fighting.
Both Armenia and Azerbaijan have in the past threatened to target strategic infrastructure in one another’s countries, such as dams or power plants, if war came. The Russian-made Tornado, or Smerch, rocket launcher that Armenia on Tuesday accused Azerbaijan of deploying, for example, has a range of more than 50 miles, enough to reach well into Armenia.
“They’ve said these things so we have to take them at face value,” Lawrence Sheets, president of Eurasian International Analytical, said in a telephone interview of the threats of strategic strikes. “We cannot discount it completely and we don’t know which direction this will go.”
On Tuesday, the Turkish foreign ministry said in a statement cited by a Turkish news agency that Istanbul would support Azerbaijan diplomatically and “on the battlefield” if needed. Russia and two other states mediating the 1990s truce, the United States and France, have called for another negotiated cease-fire.