Officials say that at least four people were killed and 14 injured in a reported "terrorist attack" at the headquarters of one of Turkey's top defense companies on Wednesday. Turkish media reported explosions and gunfire from the site around 20 miles north of the country's capital Ankara.

Turkey's interior minister Ali Yerlikaya condemned the attack on the Turkish Aerospace Industries (TUSAS) facility as "heinous." The facility manufactures fighter jets and other equipment for NATO's second largest military after the United States. Speaking to members of the media, Yerlikaya said four people had been killed, and added that 14 people had been injured, three of whom were in critical condition. Yerlikaya said: "May our martyrs rest in heaven, I wish a speedy recovery to our wounded. Our struggle will continue with determination and resolve until the last terrorist is neutralized."

There was no immediate information on who might be behind the attack, which comes as Turkey's President Recep Tayyip Erdogan is in Russian city of Kazan, where he is attending the BRICS summit along with leaders from other nations from the global south. The incident happened as Erdogan was meeting Vladimir Putin at a summit in Kazan, with the Russian leader expressing his condolences over the attack. In a statement Wednesday, Erdogan called the incident "a despicable attack" and confirmed that both attackers had been killed -- a man and a woman -- with Turkish authorities working to identify them.

Turkish Defense Minister Yaşar Güler alleged the Kurdistan Workers' Party (PKK), was behind the attack. The Kurdish separatist movement is labeled a terrorist organization by Turkey and its Western allies. Güler said in a statement on X.: "We give these PKK scoundrels the punishment they deserve every time, they do not come to their senses. I repeat what I always say, we will not let go of them until the last terrorist is eliminated. NATO stands with our Ally Turkey. We strongly condemn terrorism in all its forms and are monitoring developments closely."