Azerbaijan's ambassador to the U.S. told Axios his country is taking "appropriate defensive and precautionary measures" following an Iranian drone strike on the Nakhchivan exclave. Asked if he was worried about another attack, ambassador Khazar Ibrahim said it's "not about worrying." Instead: "We are calculating, we are looking at facts, and we are making decisions." Why it matters: The salvo, which Iran denied responsibility for, again widens a war that is just days-old and has killed many, including American troops. The latest: Baku and Washington are in close contact regarding the incident, according to Ibrahim. The two governments have a track record of cooperation, including overflight and refueling rights during the global war on terror . Zoom in: Videos seen by Axios show an explosion and black smoke near the Nakhchivan International Airport. A loud buzzing sound can be heard before impact. Iran must apologize, provide an "official explanation, ensure those responsible for this crime are held accountable, and also, of course, ensure never again these kinds of things happen," Ibrahim said. Zoom out: Azerbaijan's defense ministry said the "technical specifications" of the drones used are under investigation. Iran has leaned heavily on its Shahed, which experts have likened to a poor man's cruise missile. Go deeper: Azerbaijan wants deeper U.S. ties after Armenia peace deal