Andrey Karlov, Russia’s ambassador to Turkey, died after he was shot on Monday evening at an art exhibit in Ankara, Turkey’s capital city. The attacker, a Turkish police officer who was identified as officer Mevlut Mert Altintas, was killed, according to CNN. The gunman, who shouted “Do not forget Aleppo!”, was apparently in protest at Russia’s involvement in Aleppo. BBC News claims that leaders in Russia and Turkey call the incident a proactive terror attack, but it is not clear if the assailant has any connections with terror groups. The shooting came at a time of cooperation and friendship between Turkey and Russia, and leaders from each country vowed that they would not let the death of Karlov cause shortcomings in that friendship.