Major fighting escalates between Azerbaijan and Armenia

MOSCOW— Fighting that was reported to be fierce broke out Sunday between Azerbaijan and Armenia and quickly escalated, with the two sides claiming action with artillery, helicopter and tanks along a disputed border.

The military action centered on the breakaway province of Nagorno-Karabakh, an Armenian separatist enclave in Azerbaijan. Ethnic tensions and historical grievances in the mountainous area north of Turkey and Iran have made kindling for conflict for decades.

The fighting Sunday, however, was reportedly more severe than the typical periodic border skirmishes, and both governments used military language describing the events as war. Before Sunday, the last major escalation was in 2016.

This year, a small flareup in July went almost ignored. The mediators of a diplomatic settlement process — France, the United States and Russia — are distracted and increasingly at odds over other issues, analysts say. The conflict simmered, all but forgotten, until Sunday.

“Horrible news” from the Caucasus, Thomas de Waal, a senior fellow with Carnegie Europe, wrote on Twitter. The fighting was “already a small war.” Both sides reported dead and wounded civilians.

By early afternoon, Azerbaijan said its forces had advanced to capture seven villages and had surrounded an unspecified number of Armenian troops it was threatening to kill if they did not surrender. Armenia claimed it was holding fast and had destroyed Azerbaijani tanks and helicopters.

Also worrying observers was that Turkey’s president, Recep Tayyip Erdogan, was more openly backing Azerbaijan than during previous escalations, positioning Turkey and Russia on opposite sides of a second conflict in the region similar to their divisions over the Syrian civil war. Erdogan blamed Armenia as “the biggest threat to peace in the region.”

Nikol Pashinyan, the Armenian prime minister, declared a state of emergency and mobilized the country’s male population.

“The enemy has started an attack,” he wrote on Facebook. He said, “This aggression was preplanned.”

Azerbaijan said it was responding to cross-border artillery shelling. Its Ministry of Defense then issued a statement saying it had begun a “counterattack” with tanks, helicopters and rocket artillery.