Russian forces have become “bogged down” trying to capture the Ukrainian border town of Vovchansk, Ukraine’s top general Oleksandr Syrsky said Friday, though fighting on the eastern front remains intense. Kyiv has been trying to push back against a Russian ground assault in the northeastern Kharkiv region since May 10, when thousands of Russian troops punched through the border in a surprise attack. After initial success, “the enemy has got completely bogged down in street battles for Vovchansk and suffered very high losses in assault units,” Syrsky said, but added that fighting near the easte…