Russian authorities say the suspect in the killing of a Russian general in a car bomb explosion claimed he was paid by the Ukrainian Security Service as he pleaded guilty to terrorism charges.

Russia’s Federal Security Service accused the man of planting an explosive device in the car, but said that it was detonated from Ukraine.

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.