Heavy artillery duels and Russian airstrikes have shaken the front lines in eastern Ukraine, according to the Ukrainian General Staff’s evening situation report on Sunday. Russian artillery shelled some 20 settlements near Sumy and Kharkiv, it said. Fresh Russian attacks against Ukrainian defence lines were reported from conflict areas surrounding Donbass, with the Ukrainians successfully repelling 13 attacks near Pokrovsk and halting 17 advances by Russian troops near Kurakhove. The information could not be independently verified. Heavy fighting was reported in the area around Vuhledar, raisi…