The Ukrainian army kept up its surprise cross-border offensive into Russia for a third day on Thursday, with reports of advances despite the heavy fighting. While authorities in the Russian region of Kursk, which borders Ukraine, and the Defence Ministry in Moscow claim that Ukraine’s push has been repelled, well-connected Russian military bloggers paint a different picture. The Russian war blog Rybar, which is close to the Defence Ministry, said the Ukrainians were making gains and fortifying their positions after reserve troops were brought across the border overnight. The Russian response t…