Five Ukrainian soldiers have been killed and three injured by a land mine in the restive east.
Ukrainian military spokesman Oleksandr Motuzyanyk told reporters on July 5 that the incident occurred in the village of Donetsky, around 50 kilometers west of separatist-controlled Luhansk city.
Fighting between government troops and pro-Russian rebels has decreased since the signing of a cease-fire deal in February, but both sides accuse the other of violations.
"The situation in the conflict zone remains difficult. Rebels continue to carry out armed attacks, but their intensity is falling," said Motuzyanyk.
Motuzyanyk said that separatists had shelled government positions in villages north of Luhansk, using heavy weapons forbidden under the cease-fire deal.
Rebels accused the Ukrainian military of violating the cease-fire 32 times in the past 24 hours but reported no casualties.