The human rights NGO Amnesty International announced on Monday it had evidence of the use of cluster bombs, wide-reaching explosives that often cause extensive harm to civilian areas, in the ongoing conflict between Azerbaijan and Armenia.

Irregular military conflict erupted between the two Caucasus countries in late September over the sovereignty of Nagorno-Karabakh, a region technically under Azeri control since the Stalin era but populated lately by Armenian Christians. Locals consider Nagorno-Karabakh an independent state, which they call the Republic of Artsakh. Few states, not including Armenia itself, recognize Artsakh.

Both Yerevan and Baku claim that the other side fired the first shots triggering the current conflict. While they are not officially at war, fighting has continued uninterrupted for the past two weeks, expanding far beyond Nagorno-Karabakh and into civilian areas of both states. Extensive reports have documented that not only Armenian and Azeri soldiers are involved in the fighting, but that the Turkish government, an ally of Baku’s, is heavily involved, flying in mercenaries from the Syrian war theater. Other reports indicate that ethnic Yazidis and Greeks have joined the battlefield on Armenia’s behalf.

The Armenian government has accused Turkey of using the hostilities as an opportunity to “complete” the Armenian genocide of 1915. Despite historians near-universally agreeing on Turkey’s culpability, the Turkish government denies that it perpetrated the genocide.

The government of Artsakh denounced Azerbaijan for allegedly using cluster bombs in a video published Sunday.

The human rights commissioner of Artsakh, Artak Beglaryan, urged the world to “act” without suggesting specifics in a video showing extensive bombing of what appear to civilian areas. Azerbaijan, Beglaryan asserted, “started targeting intentionally civilian objects and population [sic].”

“Just today, Azerbaijan started heavily attacking the capital city, Stepanakert,” Beglaryan said, including “vital civilian infrastructures and civilian buildings, with heavy missiles and aviation bombs, including with cluster bombs and cluster missiles as a result of which we have civilian many casualties.”

“We now have a humanitarian disaster in Artsakh,” the commissioner said. “Stop talking and start acting, don’t be blind.”

Amnesty International issued a statement the next day saying their investigators support the claims by the de facto Artsakh government.

“Protection of civilians caught in the escalating conflict between Armenia and Azerbaijan over the Nagorno-Karabakh region must be prioritized, Amnesty International said today, after corroborating the use of banned cluster bombs in the region,” a press statement read.

“Over the weekend, footage consistent with the use of cluster munitions in the city of Stepanakert, the capital of Nagorno-Karabakh, was published by the region’s de facto authorities. They also reported an unidentified number of civilian casualties after further shelling in Stepanakert and the town of Shushi,” the statement continued.

Amnesty International added more detail to the Artsakh claims, asserting it had identified “Israeli-made M095 DPICM cluster munitions that appear to have been fired by Azerbaijani forces.”

The United Nations describes cluster bombs as “inherently inaccurate” due to the expansive territory they cover, meaning they are not significantly useful against legitimate military targets. Human rights groups have long objected to cluster bombs because they have a high rate of killing and injuring civilians; over 100 countries have signed a convention calling for a ban of the weapons.

“The use of cluster bombs in any circumstances is banned under international humanitarian law, so their use to attack civilian areas is particularly dangerous and will only lead to further deaths and injuries,” Denis Krivosheev, Amnesty International’s acting head of Eastern Europe and Central Asia, said in a statement.

Azerbaijan has responded to accusations of human rights violations by accusing Armenia of the same thing.

“The forces are deliberately attacking the city, located at a distance of more than 100 km from the ongoing hostilities zone, in which more than 100,000 people live,” a statement from the Azerbaijan human rights commissioner’s office said, referring to an alleged attack Sunday on the Azeri city of Mingachevir. “One of the missiles fell in the area of the power plant, and another — near a house where civilians live. Unfortunately, as a result of the missile’s hitting a private house, five people received injuries of varying severity and were hospitalized, and the house was heavily damaged. This industrial city has the largest dam in the South Caucasus region and power plant.”

Azerbaijan’s political factions appear united against Armenia. Ali Karimli, leader of the opposition Popular Front Party, similarly issued a statement claiming Armenian soldiers had begun planning for the bombing of power plants in Azerbaijan.

“They want to destroy the Mingachevir reservoir, to hit the Thermal Power Plant, to launch a missile at the civilians of Ganja … Armenia, which also targets Khizi and Absheron with ballistic missiles, is officially a terrorist state,” Karimli reportedly wrote on Facebook. Karimli’s remarks echoed claims by Azerbaijani Foreign Minister Ceyhun Bayramov claiming the Armenians have a “terrorist mentality.”

Azerbaijan’s accusation that Armenia is targeting their power plants follows a statement in July, long before the current hostilities began, from the Azeri Defense Ministry warning Yerevan that Azerbaijan was considering bombing the Metsamor Nuclear Power Plant in Armenia, considered the world’s most dangerous.

“The Armenian side must not forget that our army’s state-of-the-art missile systems allow us to strike the Metsamor nuclear plant with precision, which could lead to a great catastrophe for Armenia,” Vagif Dargahli, an Azeri Defense Ministry spokesman, said at the time.

The Turkish state news agency Anadolu published a report from Baku on Tuesday also citing Azeri officials claiming that Armenian soldiers had committed human rights violations in the Nagorno-Karabakh conflict.

“Armenia deliberately and non-discriminately targets the civilian settlements, Azerbaijani chief prosecutor said in a statement,” according to Anadolu. Turkey’s foreign minister, currently in Baku, called on the world to unite against Armenia.

“We will [continue to] support the territorial integrity of Azerbaijan, just as we did with Georgia, Ukraine, Syria, and Iraq’s territorial integrity,” Foreign Minister Mevlut Cavusoglu said on Tuesday.

Amnesty International addressed Azeri accusations of human rights violations, stating it did not have sufficient evidence to corroborate them.

“Azerbaijan reported that the Armenian forces attacked civilian areas in the country’s second largest city of Ganja, as well as other towns,” Amnesty noted. “While Amnesty International experts have verified that 300mm Smerch rocket artillery systems do appear to have been used by Armenian forces, the photographic and video evidence available from the Azerbaijani side does not yet allow for conclusive analysis of its specific targets, nor whether the rocket warheads contained cluster munitions.”

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