A senior Russian general has been killed in an explosion outside his apartment building in southeastern Moscow, in the latest targeted assassination reportedly carried out by Ukraine on Russian soil.

Lieutenant General Igor Kirillov, head of Russia’s Nuclear, Biological and Chemical Defence Forces (NBC), was killed on December 17 when an improvised explosive device (IED) concealed in an electric scooter detonated. Ukraine’s Security Service (SBU) claimed responsibility for the attack, marking one of the boldest assassinations in Moscow since Russia launched its full-scale invasion of Ukraine nearly three years ago.

Kirillov and his aide were killed as they exited a residential building on Ryazansky Prospekt. Russian investigators stated the IED had an explosive force equivalent to 300 grams of TNT and was remotely activated. Dashcam footage published online shows a massive blast that shook nearby cars and shattered windows.

The scooter, reportedly placed near the building’s entrance at around 4 am, points to careful planning and monitoring of Kirillov’s movements. Investigators suspect the bomb was hidden inside the scooter’s headlamp or taped to its frame. Surveillance may have been conducted from a rented apartment, a parked vehicle, or through hacked security cameras.

Kirillov, who had led Russia’s NBC forces since 2017, oversaw the country’s radiological, chemical and biological defence operations. His tenure attracted international controversy amid allegations of chemical weapons use in Ukraine, which Russia has consistently denied. In 2023, the UK and US imposed sanctions on Kirillov, accusing him of violating the Chemical Weapons Convention (CWC) and describing him as a “significant mouthpiece” for Kremlin disinformation.

Ukraine charged Kirillov in absentia with “war crimes,” alleging he was involved in the deployment of chemical agents, including chloropicrin – a choking agent dating back to World War I – against Ukrainian forces. According to the SBU, over 4,800 instances of chemical weapon use have been documented since the war began, leading to the hospitalisation of more than 2,000 Ukrainian soldiers.

Kirillov’s public statements often featured unsubstantiated claims, including accusations that Ukraine, with US support, planned to deploy “infected mosquitoes” to spread malaria among Russian troops. He was a key figure in Russia’s disinformation campaigns, denying Western accusations of chemical attacks while alleging Ukraine was producing “dirty bombs.”

The Kremlin has yet to issue a full response to the assassination. However, key Russian officials have strongly condemned the attack. Deputy Chairman of the Russian Security Council Dmitry Medvedev called the bomb a “terrorist attack,” stating that the “Kyiv regime” is delivering “cowardly attacks on civilians in cities and towns.”

“Attempts to intimidate our nation, stop the Russian offensive or sow fear are doomed. Certain punishment awaits Banderite Nazis, including the top military and political leaders of a crumbling country,” Medvedev said.

Russian Foreign Ministry Spokeswoman Maria Zakharova also blamed the West for enabling Ukraine’s “crimes,” writing on Telegram: “General Igor Kirillov and his aide were killed in a planned manner, killed in front of an apartment building at a time when people were going to work, and children were going to school or kindergarten.”

Kirillov’s killing is part of an ongoing series of high-profile attacks attributed to Ukraine’s SBU and military intelligence services. In the past year, Ukrainian operatives have reportedly targeted Russian naval officers, missile scientists and other officials.

Prior to 2024, the most high-profile assassinations conducted by Ukraine were targeted at pro-war propagandists. In July 2022, journalist Darya Dugina, daughter of nationalist ideologue Alexander Dugin, was killed in a car bombing. While Kyiv denied involvement, Russia’s Federal Security Service (FSB) accused a Ukrainian citizen, Natalia Vovk, of planting the device.

Months later, prominent military blogger Vladlen Tatarsky was killed in a St Petersburg cafe bombing. Darya Trepova, a political activist accused of handing him the explosive device, claimed she acted under orders from a Ukrainian contact. She was later sentenced to 27 years in prison.