Relations between Azerbaijan and Russia have deteriorated sharply after two Azerbaijani citizens, brothers Ziyaddin and Huseyn Safarov, died in Russian police custody during mass arrests in Yekaterinburg on 27 June. Autopsies carried out in Baku concluded the men succumbed to severe blood loss and shock caused by extensive physical trauma, contradicting Russian claims that one brother suffered a heart attack while the other’s death remains under investigation. Azerbaijan’s Prosecutor General opened a murder inquiry and the government suspended all Russian-linked cultural events on 29 June. A planned visit by Russian Deputy Prime Minister Alexei Overchuk and a parliamentary meeting in Moscow were called off. Police in Baku also raided the offices of Sputnik Azerbaijan and later detained at least eight Russian nationals on cyber-crime and drug-trafficking charges, some of whom appeared in court with visible injuries. The Kremlin summoned Azerbaijan’s ambassador, accusing Baku of deliberately undermining bilateral ties and vowing to protect Russian citizens “through diplomatic channels and all available means.” Moscow media said six ethnic Azerbaijanis with Russian passports have been remanded in custody over decades-old murder cases, while an Azerbaijani diaspora leader in Yekaterinburg was briefly detained amid the widening dispute. The standoff deepens Moscow’s challenges in the South Caucasus, where its role as the region’s dominant power has already been eroded by the Armenia-Azerbaijan peace process advancing without Russian mediation. Analysts warn that further escalation could weaken Russia’s influence over a strategic corridor that carries Caspian energy to Europe and heighten regional volatility at a time when the Kremlin is pre-occupied with its war in Ukraine.