KIEV, Ukraine (AP) — A top Ukrainian security official says government troops have cleared more than a dozen towns of armed pro-Russia separatists and now control two-thirds of the eastern regions at the center of the insurgency.

National security council secretary Andriy Parubiy said Friday that Ukrainian forces are still attacking rebel positions with artillery and planes. He said 17 villages had been secured by government forces since a unilateral cease fire expired Monday.

He said Ukrainian forces now control 23 of 36 local regions within Donetsk and Luhansk provinces, two regions along the Russian border that have declared independence from the government in Kiev.

The rebels are still fighting back. Rebels shelled the Donetsk airport overnight and an AP reporter said a radar or communications tower there was still burning in the morning.