NATO Secretary General Jens Stoltenberg said the early results of an investigation indicated that an explosion on Polish territory Tuesday, "was likely caused by a Ukrainian air defense missile fired to defend Ukrainian territory against Russian cruise missile attacks." Stoltenberg said NATO's investigation was ongoing after a meeting of NATO allies in Brussels. Follow Bloomberg for business news & analysis, up-to-the-minute market data, features, profiles and more: http://www.bloomberg.com/ Connect with us on... Twitter: https://twitter.com/business Facebook: https://www.facebook.com/bloombergbusiness/ Instagram: https://www.instagram.com/quicktake/?hl=en