Russia has arrested a suspect over the killing of a senior Russian general in a scooter bomb attack in Moscow claimed by Ukraine.

Lt. Gen. Igor Kirillov, head of the military’s nuclear and chemical weapons division, was killed early on Tuesday along with his aide, Ilya Polikarpov.

Russia’s Investigative Committee said a 29-year-old suspect from Uzbekistan and been “recruited by Ukrainian special forces” and paid $100,000 for the assassination.

Kirillov, 54, is the most senior Russian officer to be assassinated during Russia’s invasion of Ukraine.

Ukraine’s security service, the SBU, has claimed Russia used chemical weapons more than 4,800 times under the general’s leadership.

In October, the UK placed sanctions on Kirillov, saying he had overseen the use of chemical weapons in Ukraine and acted as a “significant mouthpiece for Kremlin disinformation”.