Investigators in Moscow are examining the deaths of two men on Ryazansky Prospekt, a road located southeast of the Kremlin.

According to Reuters, a bomb concealed in an electric scooter killed a senior Russian general in charge of nuclear protection forces in Moscow on Tuesday, Russia's investigative committee announced.

Lieutenant General Igor Kirillov, the head of Russia's Nuclear, Biological and Chemical Protection Troops, was killed outside an apartment building on Ryazansky Prospekt, a major road located approximately 7 km (4 miles) southeast of the Kremlin.

"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," the investigative committee stated.

Photographs shared on Russian Telegram channels depicted a shattered building entrance, strewn with rubble, and two bodies lying on blood-stained snow.

Russia's radioactive, chemical, and biological defense troops, known as RKhBZ, are specialized forces trained to operate in environments contaminated by radioactive, chemical, or biological hazards.