Fighting has broken out between Armenia and Azerbaijan, and the Armenian government has declared martial law and total military mobilization.

Martial law and General mobilization will be declared in #Armenia. @NikolPashinyan: I call on the personnel attached to the troops to report to their territorial military recruitment offices. For the sake of the homeland, for the sake of victory — Government of Armenia (@armgov) September 27, 2020

The neighboring nations, both former Soviet republics, have been mired in a decades-long standoff over the contested Nagorno—Karabakh region, which is internationally recognized as part of Azerbaijan, but has a majority ethnic Armenian population that has been running its own affairs since Azerbaijani forces were pushed out during a war in the 1990s. A ceasefire was brokered in 1994, but there have been flare-ups since, and Sunday's escalation appears to be the worst since 2016, Al Jazeera reports.

Both sides have reported civilian deaths and blamed the other for instigating the fighting, while providing conflicting reports on how the clash has played out. The Armenian Defense Ministry said Azerbaijan launched an attack on civilian settlements Sunday morning, and in response Armenia shot down two helicopters and three drones and destroyed three tanks. Azerbaijan only acknowledged that one helicopter had been lost while the crew survived, and a defense ministry spokesperson said several villages in Nagorno-Karabkh "which were under enemy occupation for many years have been liberated."

Russia, France, and the European Union were among the governments that have called for an end to the violence and an immediate return to the ceasefire and negotiations. Read more at BBC and Al Jazeera. Tim O'Donnell