NIZHYN, Ukraine—The Ukrainian platoon was digging in desperately along a tree line in this country’s east when grenades began exploding around it and Russian soldiers crept in from the left.
The 16 Ukrainians fought back as best they could but couldn’t stop the Russians from overrunning a position held by five of their number, including Pvt. Oleksandr Matsievskiy, a 42-year-old electrician who lived with his mother and was new to front-line combat.