Igor Kirillov, a senior general in charge of Russia’s nuclear defence forces, was killed on Tuesday in a bomb blast in Moscow.
A source in the Security Service of Ukraine (SBU), talking to Al Jazeera, has claimed responsibility for the bombing.
Here’s what you should know:
What do we know so far?
During the early hours of Tuesday, Kirillov was killed by a bomb hidden in an electric scooter outside an apartment building on Ryazansky Prospekt, Russia’s investigative committee said in a statement. The attack site was 7km (4 miles) southeast of the Kremlin.
The explosive device “had a capacity of some 300 grams in TNT equivalent”, Russia’s TASS news agency reported, quoting a law enforcement official.
Russian media reported that the bomb was remotely operated.
Pictures from the scene show a scooter with its handlebars blown off and damage to the entrance alongside the outside walls of the building.
Kirillov’s assistant was also killed.
“Two body bags could be seen on the street,” said Al Jazeera’s Yulia Shapovalova, reporting near the site of the blast. “Judging by the shattered windows, the blast wave reached at least the fourth floor, with about 10 apartments reportedly damaged.”
Who was Kirillov?
Kirillov, who was 54 at the time of his death, had served as chief of the Troops of Radiological, Chemical and Biological Defence since April 2017.
Special forces in the Russian military, they operate under conditions of radioactive, chemical and biological contamination.
Kirillov was married with two sons.
The Russian general was under sanctions from several countries, including the United Kingdom and Canada, for his role in the war in Ukraine.
What has Russia said?
“Igor Kirillov, the head of the radiation, chemical and biological protection forces of the armed forces of the Russian Federation, and his assistant were killed,” said the Russian investigative committee.
Russia’s investigative committee announced that a criminal case has been opened.
Svetlana Petrenko, spokeswoman for the committee, said in a statement that Moscow is treating the bombing as a “terrorist” attack.
Maria Zakharova, foreign ministry spokeswoman, paid tribute to Kirillov. She said he worked “fearlessly” for “the motherland” to uncover the West’s chemical weapons-related crimes and other crimes.
Dmitry Medvedev, deputy chairman of Russia’s Security Council, said, “Realising the inevitability of its military defeat, [Ukraine] launches cowardly and despicable strikes in peaceful cities.”
What has Ukraine said?
SBU sources have claimed responsibility for the killing with several news media outlets, but Ukraine has not officially commented.
A Ukrainian law enforcement official told Politico more on condition of anonymity.
“Kirillov was a war criminal and an absolutely legitimate target since he gave orders to use banned chemical weapons against the Ukrainian military. Such an inglorious end awaits all who kill Ukrainians. Retribution for war crimes is inevitable,” the unnamed official told Politico.
On Monday, the SBU accused Kirillov of using banned chemical weapons during Russia’s full-scale invasion of Ukraine that began in February 2022.
In a statement on Monday, the SBU said Russia’s forces have used different types of banned chemical munitions against Ukraine more than 4,800 times. This included K-1 combat grenades.
Which other Russian officials have been killed during wartime?
Russia has accused Ukraine of orchestrating a string of high-profile wartime assassinations.
Ukraine usually denies a role in attacks within Russia or Crimea, but its officials often celebrate them in posts on social media.
In November, senior Russian naval officer Valery Trankovsky was killed in a car bombing in Crimea. In this case, a source in Ukraine’s security services told the French news agency AFP that Ukraine was behind the assault.
In August 2022, Darya Dugina, the daughter of Russian ultranationalist Alexander Dugin, was killed in a car bombing. Ukraine denied any role in her killing.
In April 2023, the pro-war Russian blogger Vladlen Tatarsky was killed in a bombing at a Saint Petersburg cafe. Ukraine did not claim responsibility, instead blaming domestic infighting.
In July 2023, submarine commander Stanislav Rzhitsky, who was accused of war crimes by Ukraine, was shot dead in a Krasnodar park. Again, Kyiv denied a role.