Kyiv has found itself increasingly vulnerable. A huge attack cut power to 600,000 people there, and a Pentagon-funded satellite program appeared to be curbed without warning.

Bulgaria on Wednesday said Russia was likely behind drone attacks that struck four ships in the Black Sea in the past week, sinking two, but there was no way of proving Moscow's culpability. Rescuers are still searching for 11 crew members missing after drone strikes on Tuesday sank two ships in Bulgaria's exclusive economic