A Russian intelligence agency says it has detained a suspect in the killing of a senior general in Moscow.
The suspect was described as an Uzbek citizen recruited by Ukrainian intelligence services.
Russia’s Federal Security Service, or FSB, did not name the suspect, but said he was born in 1995.
According to a statement by the FSB, the suspect said himself that he was recruited by Ukrainian special services.
Lt Gen Igor Kirillov was killed on Tuesday by a bomb hidden in a scooter outside his apartment building in Moscow, a day after Ukraine’s security service levelled criminal charges against him.
A Ukrainian official said the service carried out the attack.
Lt Gen Kirillov was the chief of the military’s nuclear, biological and chemical protection forces. His assistant also died in the attack.
Lt Gen Kirillov (54) was under sanctions from several countries, including the UK and Canada, for his actions in Moscow’s military operation in Ukraine.
On Monday, Ukraine’s Security Service, or SBU, opened a criminal investigation against him, accusing him of directing the use of banned chemical weapons.
Russia has denied using any chemical weapons in Ukraine and, in turn, has accused Kyiv of using toxic agents in combat.
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Lt Gen Kirillov, who took his current job in 2017, was one of the most high-profile figures to level those accusations.
He held numerous briefings to accuse the Ukrainian military of using toxic agents and planning to launch attacks with radioactive substances – claims that Ukraine and its western allies rejected as propaganda.
The bomb used in Tuesday’s attack was triggered remotely, said Russian news reports.
Images from the scene showed shattered windows and scorched brickwork.
Ly Igor Kirillov was killed on Tuesday by a bomb hidden in a scooter outside his apartment building in Moscow, a day after Ukraine’s security service levelled criminal charges against him