Armenia and Azerbaijan accuse each other of breaches of the ceasefire at the joint border earlier on Friday. On September 14, a ceasefire between the two countries went into effect after the September 13 ceasefire agreement collapsed right after it went into effect.

From the Armenian end, the Defense Ministry stated that Azeri forces targeted the Armenian position east of the country which led to "retaliatory actions." The ministry added that the fire was ceased and that no losses were accounted for from the Armenian side.

"At 07:40 [local time, 03:40 GMT] on September 23, Azerbaijani forces once again violated the ceasefire regime, opening fire ... at Armenian positions on the eastern direction of the Armenian-Azerbaijani border," the Armenian Defense Ministry said in a statement.

In Azerbaijan, on the other hand, the defense ministry argued that Armenia shelled three of the Azeri forces' border positions in separate regions.
 
"From the evening of September 22 until the morning of September 23, Armenian armed forces units on the Azerbaijani-Armenian state border fired at the positions of the Azerbaijani army in the direction of the settlements of [three border regions] ... The Azerbaijani army units took adequate response measures," the Azerbaijan Defense Ministry said in a statement.

CSTO mission in Armenia

Armenian Foreign Minister Ararat Mirzoyan said on September 14 that the Collective Security Treaty Organization (CSTO) mission is expected to arrive on September 15 at the  Armenia-Azerbaijan border, the site of recent violent clashes which saw the loss of tens of troops on both sides. 

"Our request was duly discussed at a meeting of the CSTO Council, a decision was made to send a mission, and we hope that the mission will arrive tomorrow," Mirzoyan said, despite the recent invocation of article 4 of the CSTO charter to evict Azeri troops from Armenia's territory and restore the territorial integrity of the Republic of Armenia after Blinken had promised to provide US assistance to Armenia. 

The mission headed by the Secretary-General is sent to Armenia to estimate the situation due to reescalation on the Armenia-Azerbaijan border.

Tensions erupt over Karabakh

Clashes erupt every now and then between both sides despite a Russian-backed ceasefire agreement. Last month, tensions erupted over Nagorno-Karabakh as three soldiers were killed and Azerbaijan said it had taken control of several strategic heights in the disputed region.

Armenia and Azerbaijan fought two conflicts over Azerbaijan's Armenian-populated area of Nagorno-Karabakh, one in 2020 and one in the 1990s.

Six weeks of violence in the autumn of 2020 claimed over 6,500 lives and ended with a ceasefire accord sponsored by Russia, which sent 2,000 peacekeepers to monitor the truce as tensions persist despite the ceasefire deal.

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