The shelling came as attacks have intensified in the last month after a period of relative calm in the conflict between Ukraine forces and Russian-backed separatists that has killed some 13,000 people since 2014.

The family were injured after their house in the village of Mariinka, 20 kilometres (12 miles) southwest of the rebels' de facto capital Donetsk, came under artillery fire, the defence ministry said.

The war in the east erupted after a popular uprising ousted Ukraine's pro-Kremlin president and Russia annexed Crimea.

In the first five months of this year, civilian casualties were "among the lowest for the entire conflict period," the United Nations monitoring mission in Ukraine said in a report published Thursday, but the number of civilian casualties has risen again this month.

A nine-year-old girl was being treated in hospital for concussion and a trauma injury to her stomach after the attack at 5 am local time (0200 GMT), the defence ministry said.

Two women from the same family were also being treated in hospital along with an 86-year-old man, who received the most severe injuries.

Ukrainian soldiers pulled the family from the ruins and took them to hospital, the military said.

Several other houses and outbuildings were also damaged.

Kiev and its Western backers accuse Russia of funnelling troops and arms across the border to fan the flames of the conflict. Moscow has denied the claims despite overwhelming evidence to the contrary.