Fresh clashes erupted between Azerbaijan and Armenia on Wednesday, a day after nearly 100 soldiers were killed in the deadliest fighting between the ex-Soviet republics since 2020.

At least 49 Armenian and 50 Azerbaijani military personnel were killed on Tuesday in the clashes, with both Yerevan and Baku blaming each other for the fighting which prompted an appeal for calm from Russian President Vladimir Putin.

The clashes have raised fears of another major armed conflict in the former Soviet Union while Russia’s military is tied up with the invasion of Ukraine.

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A full-fledged conflict between Armenia and Azerbaijan would risk dragging in powers such as Russia and Turkey, and destabilise an important corridor for pipelines carrying oil and gas just as the confrontation over Ukraine disrupts energy supplies.

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The Armenian defence ministry on Wednesday accused Azerbaijan, which is backed politically and militarily by Turkey, of firing artillery, mortar and small arms in a fresh attack.

“The situation on the Armenian-Azerbaijani border remained tense,” it added, restating Armenia’s position that Azerbaijan launched attacks on its sovereign territory.

Azerbaijan accused Armenia, which is in a military alliance with Moscow and home to a Russian military base, of firing mortars and artillery against its military units.

“Our positions are periodically being fired against at the moment,” Azerbaijan’s defence ministry said. “Our units are taking the necessary response measures.”

Reuters was unable to immediately verify battlefield accounts from either side.