茲布魯奇河
As the UHA suffered from a lack of ammunition, on 28 June a better equipped and much larger Polish force broke through the Ukrainian lines at Janczyn and forced the UHA to retreat to the Zbruch River. Eventually the Ukrainians were forced back toward the Dnipro Valley then controlled by the Ukrainian People's Republic, another nascent Ukrainian state that did not hold the same territorial aspirations as its ethnic neighbor.