Fighting rages in Donetsk Friday around the strategic airport played by the Ukrainian army and pro-Russian separatists, who have been, according to Kiev, reinforcements of Russia, following the death in a bombing of an employee Swiss Red Cross.

Two loud bangs rang out Friday morning near the center of Donetsk, which resumed Thursday with violence, according to a team of AFP.

Intensified fighting and shelling of residential areas in the rebel stronghold having been eleven deaths in two days has been denounced as a “dangerous escalation” by the Office of the Secretary General of the UN, one month after the conclusion of a fragile truce between Kiev, Moscow and pro-Russian separatists.

The Ukrainian military spokesman Andrii Lysenko has reported for Donetsk airport, still controlled by him by the Ukrainian army after two rebel attacks yesterday with tanks “constant fighting”.

He said Russia had sent reinforcements “tanks, heavy weapons and soldiers” pro-Russian separatists to attack the airport and drones “directed by Russian specialists.” Two Ukrainian soldiers were killed and nine wounded in the past 24 hours, he has announced.

Kiev as Westerners accuse the Kremlin of throwing oil on the fire in the conflict more than five months has left more than 3,200 dead and half a million refugees and displaced persons.

NATO said this week that “hundreds” of Russian soldiers were still in the east of Ukraine, while the latter Minsk Agreement provides for the withdrawal of all foreign fighters.

The new Secretary General of NATO, Jens Stoltenberg, called Wednesday “a real change in the actions of Russia,” saying that the country “maintains its ability to destabilize Ukraine.” Moscow denies any involvement in the Ukrainian conflict.

“Despite the peace initiatives of the President of Ukraine, the Russian aggression against our state has not stopped,” said Friday the president of the Ukrainian parliament, Oleksandr Turchinov.

“The cease-fire has been violated more than 1,000 times, soldiers and civilians continue to die,” said he complained at a meeting with religious leaders.

About 70 Ukrainian civilians and soldiers have died since the beginning of the truce on Sept. 5, according to an AFP count.