Updated

Ukrainian authorities say three of its troops have been killed and four injured in eastern Ukraine in an apparent flare-up of fighting between government troops and Russia-backed separatists.

The press office for the Ukrainian government's operation in the east said early Wednesday their positions came under fire 65 times in the past 24 hours. It appeared to be the worst loss of lives reported in weeks.

The armed conflict in Ukraine's industrial heartland has claimed more than 9,900 lives since it began in 2014. In a move that further cements Russia's control over parts of eastern Ukraine, Moscow announced Tuesday it would supply electricity to rebel-controlled areas after the Ukrainian government cut off power because of a heavy backlog of unpaid bills.