A truce was signed in February after the conflicts between Russia-backed separatist rebels and Ukrainian Government.
According to an UN report, 6,400 people were killed because of the conflict between Russia-backed separatist rebels and Ukraine since April 2014.
Artillery fire killed three people in the front line town of Horlivka and two in the rebel capital of Donetsk, according to Donetsk News Agency. The Ukrainian Security and Defense Council also reported two troops killed and six injured overnight.
Both sides have withdrawn artillery guns, tanks and other heavy weapons under the terms of the Minsk peace agreement in mid-February, but people are still regularly killed in sporadic outbursts of fighting.
Both sides regularly accuse the other of violating the terms of the agreement and casualties are reported almost daily.
President Vladimir Putin did not comment about recent shelling, however he implied that current Ukrainian government is not free to make its own decisions.
Also, “ the country is being managed from outside” said Putin.
On the other hand, Russian Foreign Minister Sergey Lavrov accused the Ukrainian government with his recent speeches.
"We're worried about events of the recent days, which look very much like preparation for fresh hostilities," said Lavrov.
US Secretary of State John Kerry urged an immediate ceasefire.
"The secretary expressed grave concern about the sharp increase in separatist attacks in Eastern Ukraine, and urged an immediate ceasefire and full implementation of Minsk obligations," the State Department said in a statement.