A Ukrainian counterattack in the north continues to disrupt Russian supply lines.
Russian forces "did not conduct offensive operations in the Kharkiv direction. The main efforts were focused on preventing the advance of our troops in the area of the settlement of Vesele," the Ukrainian General Staff said on Friday.
The Ukrainians have taken a number of villages in this area east of Kharkiv.
CNN reported early on Friday that at least three bridges in the area had been demolished, according to satellite imagery. It seems likely that Russian units destroyed the bridges in an effort to protect their supply lines from further Ukrainian advances.
Elsewhere in Kharkiv region, the Russians appear to be using artillery sporadically but with deadly effect.
On Thursday, shelling of the town of Derhachi killed two people, according to the local administration, and destroyed the humanitarian center and medical facilities.
Derhachi is about 10 miles (16 kilometers) north of Kharkiv, which is Ukraine's second-largest city.