A military spokesman reported six soldiers killed and 18 others wounded over the past day, adding that a civilian was left dead in a rebel strike on a checkpoint near Fashchivka in the Lugansk region.
City officials in hard-hit Donetsk earlier said four civilians died after shelling sparked a fire at a warehouse there.
"In the past day, six Ukrainian soldiers were killed. Eighteen more were wounded," military spokesman Andriy Lysenko said.
Clashes have also hit other areas in the east as part of an upsurge in violence in recent days in a conflict that has killed more than 4,800 people.