Three people died, including a NATO representative, in an explosion at a military installation in northern Ukraine, the Ukrainian defence company Ukroboronprom said on Friday (July 29). <br /> <br />The explosion occurred on the afternoon of Thursday (July 28) while a missile was being unloaded from a vehicle, the company said in a statement. Two other workers were injured, it added. <br /> <br />Local media said the representative from the North Atlantic Treaty Organization was a Ukrainian who monitors the disarming of Soviet-era weapons, a process partly financed by NATO. <br /> <br />A later investigation by the Ukrainian military was quoted as saying the cause of explosion may have been negligence in dealing with arms. <br /> <br />Ukraine, the western-most outpost of the former Soviet Union, inherited thousands of tonnes of obsolete ammunition and weapons that is due to be destroyed.