Bogged down in east Ukraine, Putin’s Russia eyes ‘opportunistic’ gains in northern Sumy

Russia’s grisly Palm Sunday attack on the city of Sumy has focused attention on the northern Ukrainian region where Kyiv says an expected Russian spring offensive is already under way. Experts say the push into Sumy is aimed at stretching Ukraine’s defensive lines and projecting an image of Russian progress on the front – even as Moscow’s war of attrition in the east grinds to a bloody stalemate.