The place where Lt. General Igor Kirillov, the head of Russia's Nuclear, Biological, and Chemical Defence Forces, and his assistant were killed by an explosive device in Moscow, Russia, on December 17, 2024. (AP)

"The liquidation of Lt. Gen. Igor Kirillov, chief of the Russian Armed Forces’ radiation, chemical, and biological defense troops, is a special operation by the SBU," a source within Ukraine's SBU security service told AFP on Tuesday.

Ukrainian officials have confirmed their involvement in the assassination of Kirillov which took in Moscow earlier today.

Ukraine's fingerprints evident: State Duma

After announcing that Russia's security apparatus has launched an investigation into the assassination of Kirillov, the first deputy chairman of the Russian State Duma Defense Committee, Alexey Zhuravlev, announced earlier today that "All those responsible must be punished."

The Russian official further explained that "hardly anyone doubts" that this crime was carried out by Ukraine, saying, "They are proud of it, and what is most terrible is that they encourage terrorism in the West."

Furthermore, Zhuravlev also added that "the criminal nature of the Kiev regime is obvious. It is a terrorist state led by an illegitimate president [Volodymyr Zelensky] - a Nazi."

The details

A criminal investigation has been launched in connection with the incident according to the Russian Investigative Committee.

The explosion on Ryazanskiy Prospekt reportedly killed two people early on Tuesday, both military personnel, Kirillov and his assistant.

On Telegram, the committee announced that "according to the investigation, on the morning of December 17, an explosive device, planted in a scooter parked next to the entrance of a residential building, was detonated on Ryazanskiy Prospekt in Moscow. As a result, the head of the radiation, chemical, and biological defense troops of the armed forces of Russia, Igor Kirillov, and his assistant were killed."

In turn, a representative of an emergency security apparatus reported that "Video footage from the explosion site on Ryazanskiy Prospekt was seized," and that the Russian security forces were examining it.

'Fake solutions' will not end Russian op. in Ukraine: Nebenzya

Russia will pursue its objectives in Ukraine strategically as long as Western solutions to the conflict remain "fake" Russian Permanent Representative to the United Nations Vasily Nebenzya stated at a UN Security Council meeting.

He emphasized, "Russia's conditions are clear and logical, and they have nothing in common with those fake solutions that fail to eliminate the threat posed to Russia by the Kiev regime."

Nebenzya also warned that Russia would respond decisively to actions by Ukrainian authorities. "As long as this is taking place, we will continue to pursue the goal of our special military operation in a strategic manner," he said, adding, "We will respond to the Kiev regime's provocations in the same way we did on December 13."