A Russian attack plane has been shot down, a Ukrainian army brigade has reported.
The 110th separate brigade said the Su-25 had been destroyed in Donetsk.
It said it was the fourth Su-25 to have been shot down, adding it will keep issuing "flaming fines" to Russia for crossing into Ukraine.
"Our sky will become hell for the occupant pilots. Our squad number will be a nightmare for them," it added.
