Donetsk airport
Donetsk airport
At least 15 people have been killed in the worst fighting in eastern Ukraine since a ceasefire was declared between government and pro-Russia forces three weeks ago, official sources say.

Presidential aide, Yury Biryukov, said in Kiev that the shelling erupted around the airport of the flashpoint city of Donetsk -- which is currently being controlled by pro-Russians - and left seven government soldiers dead and nine others injured.

Pro-Russia sources said five of their fighters died and eight were injured in the shelling.

According to the City Council of Donetsk, three civilians were also killed in the conflict.

Several residential, industrial, and government buildings were also destroyed over the weekend.

Since the five-month-long conflict in eastern Ukraine officially came to an end on September 5, both sides have been accusing one another of violating the ceasefire pact.

Ukraine's mainly Russian-speaking regions in the east have witnessed deadly clashes between pro-Russia forces and the Ukrainian army since Kiev launched military operations to silence the pro-Russians in mid-April.

Violence intensified in May after the two flashpoint regions of Donetsk and Lugansk held local referendums in which their residents voted overwhelmingly in favor of independence from Ukraine.