Russia launched a sweeping drone assault and airstrikes across Ukraine early Sunday, killing at least four people, officials said, after U.S. President Donald Trump cast doubt over Russian President Vladimir Putin’s willingness to end the war.

Russia accused Ukraine of being behind the car bombing near Moscow that killed General-lieutenant Yaroslav Moskalik.

Russia’s Foreign Ministry called it a “terrorist attack,” and surveillance footage showed a car exploding as Lt. Gen. Yaroslav Moskalik was approaching it in a Moscow suburb.