The eastern Donetsk region's self-proclaimed deputy defence minister Eduard Basurin told AFP that three women died when Ukrainian forces shelled Gorlivka, a rebel bastion about 30 kilometres (20 miles) northeast of Donetsk city.
The Kiev-appointed governor of the neighbouring war-torn province of Lugansk reported the death of one soldier in a mortar attack on the edge of the disputed demarcation line between the two forces.
Monitors from the Organization for Security and Co-operation in Europe (OSCE) have accused both Kiev and separatist fighters of breaching a February ceasefire agreement that required the withdrawal of heavy weapons from a mutually-agreed buffer zone.