Unmanned vehicles dominate the battlefield in Ukraine—laying mines, delivering ammunition and medication, even evacuating casualties.

Ukraine’s Security Service said Sunday they had killed Russian special service agents suspected of gunning down a fellow officer in Kyiv earlier this week, saying it believed Russia’s Federal Security Service was responsible.

Russia launched its largest drone and missile bombardment of Ukraine overnight into Wednesday, according to Ukrainian President Volodymyr Zelenskyy.

Between January and June, the number of Russian drone and missile attacks exceeded 23,000, a roughly 605% increase compared to the same period last year.

Russia hit the Ukrainian city of Odesa with a daytime drone strike on Friday. At least 11 people were injured, according to authorities.