The Ukrainian government says one soldier has been killed and several troops wounded in the country's east in what seems to be a violation of a recently brokered armistice.

Both sides in the deadly conflict between government forces and Russia-backed separatists had agreed to observe a cease-fire with the start of the Orthodox Easter and May Day holidays. The armistice was supposed to go into effect at midnight Saturday.

Sunday is Easter under the Orthodox Christian calendar.

Oleksandr Motuzyanyk, spokesman for Ukraine's operation in the east, said Sunday that the separatists had shelled its positions overnight at several locations, including the suburbs of the rebel stronghold of Donetsk.

The separatist mouthpiece Donetsk News Agency reported shelling by government forces but said it occurred before the midnight deadline.