"There is reason to believe that Ukrainian special services were involved," a Russian Foreign Ministry spokesperson said.

The Russian Federal Security Service (FSB) has reported that an alleged agent of the Ukrainian special services has been detained on suspicion of murdering Lieutenant General Yaroslav Moskalik, Deputy Chief of the Main Operational Directorate of the General Staff of the Russian Armed Forces.

A man alleged to have been recruited by a Ukrainian intelligence agency has been arrested by Russia's Federal Security Service, or FSB, in connection with the car bombing death of a Russian general last week.