MOSCOW, December 19. /TASS/. The Russian Federal Security Service said it is working with its counterparts in Uzbekistan to identify accomplices in the assassination of Chief of Russia’s Radiation, Chemical and Biological Protection Troops Lieutenant-General Igor Kirillov and his aide Ilya Polikarpov.

"The Federal Security Service, in close cooperation with the special services of the Republic of Uzbekistan, is conducting a set of investigative measures to identify possible accomplices and other circumstances related to the detonation of the improvised explosive device that killed Chief of Russia’s Radiation, Chemical and Biological Protection Troops Lieutenant-General Igor Kirillov and his aide, Major Ilya Polikarpov," the agency said. "The special services of the Republic of Uzbekistan are doing all they can to provide assistance."

According to the agency, also known by its Russian acronym FSB, the joint efforts are part of an investigation into a case that the Russian Investigative Committee started on charges of a terrorist attack, murder, illegal possession of explosives, and illegal manufacturing of explosive devices.

Earlier, an Uzbek national named Akhmadzhon Kurbonov was detained and arrested in the case of the assassination of Kirillov and his aide. He said he had been recruited by Ukrainian special services for a reward of $100,000 and a chance to relocate to an EU country.

Uzbek President Shavkat Mirziyoyev spoke with Russian President Vladimir Putin by phone and expressed condolences over Kirillov's death, describing the attack as a vile terrorist attack.

The general and his aide were killed in a detonation of an explosive device that had been planted in an electric scooter parked near the entrance of a residential building in Moscow.