EDILLI, Azerbaijan: Azerbaijan said Wednesday it has discovered what it claims is a mass grave of its soldiers allegedly executed by Armenian separatist forces during the 1990s war over the disputed Nagorno-Karabakh region.

Baku and Yerevan fought two wars – in 2020 and in the 1990s – over the contested mountainous region of Nagorno-Karabakh, an Armenian-populated enclave of Azerbaijan.

“A mass grave of Azerbaijani servicemen tortured and executed during the first Karabakh war was discovered in the village of Edilli,” Hikmet Hajiyev, the foreign policy adviser to President Ilham Aliyev, said Wednesday on Twitter.

He said “4,000 Azerbaijani troops and civilians remain missing since the (1990s) war and Armenia refuses to disclose the locations of mass graves.”

Namig Efendiyev of the state commission for prisoners of war told AFP that “25 human remains were discovered since February at the mass grave.”

Baku’s announcement came days after Armenia accused Azerbaijani troops of war crimes committed during deadly border clashes last month.

In September, at least 286 people were killed on both sides before a US-brokered truce ended the worst clashes since the neighbours’ 2020 war.

On Sunday, Armenia’s foreign ministry said “numerous videos regularly (published) by Azerbaijani users on social media demonstrate the war crimes,” including extrajudicial killings and torture of Armenian POWs and desecration of corpses.

Azerbaijan said on the same day that its military prosecutor’s office had launched a probe into alleged war crimes committed by Baku forces.

On Tuesday, Azerbaijan freed 17 Armenian prisoners of war following US mediation.

The six-week war in 2020 claimed the lives of more than 6,500 troops from both sides and ended with a Russian-brokered ceasefire.

Under the deal, Armenia ceded swathes of territory it had controlled for decades, and Moscow deployed about 2,000 Russian peacekeepers to oversee the fragile truce.

With Moscow increasingly isolated on the world stage following its February invasion of Ukraine, the United States and the European Union have taken a leading role in mediating the Armenia-Azerbaijan normalisation process.

On Sunday, the foreign ministers of Armenia and Azerbaijan met in Geneva where they began drafting the text of a future peace treaty.

When the Soviet Union collapsed in 1991, ethnic Armenian separatists in Nagorno-Karabakh broke away from Azerbaijan. The ensuing conflict claimed around 30,000 lives.