Russia detains suspect in Moscow blast that killed general

GMA: Russian investigators detained a 29-year-old citizen of Uzbekistan in connection with Tuesday's assassination of a general in Moscow, an attack in a residential neighborhood for which Ukraine claimed credit.

Lt. Gen. Igor Kirillov was killed by an explosive device that appears to have been hidden in a parked scooter and set off by remote control, Russian state-affiliated media TASS reported. The explosion also killed an aide accompanying him.

Kirillov was the head of Russia's radiation, chemical and biological protection troops. Sources told ABC News that the Security Service of Ukraine was behind the killing. Kirillov is the most senior Russian military official assassinated by Ukraine.

The suspect had been recruited by Ukrainian intelligence officers, Russian police said as they announced the arrest.

"On their instructions, he arrived in Moscow and received an improvised explosive device," police said. "He placed it on an electric scooter, which he parked at the entrance of the apartment building where Igor Kirillov lived."

The suspect had used a carshare to rent a car and installed a video camera in the vehicle, which was then parked near where the blast went off, police said.

PHOTO: People walk outside an apartment building before a blast in which Lieutenant General Igor Kirillov was killed, in Moscow, Russia, in this still image obtained from a social media video on Dec. 17, 2024. (Social Media via Reuters)

"The footage from this camera was broadcast online to the organizers of the terrorist attack in the city of Dnipro," Russia's Investigative Committee said. "After a video signal was received about the exit of the servicemen from the entrance, the explosive device was remotely activated by them."

Russia claimed the suspect had been offered payment of $100,000, along with an agreement that they would be allowed to move to a European country.

ABC News' Joseph Simonetti, David Brennan and Patrick Reevell contributed to this report.