Igor Kirillov, chief of the Troops of Radiological, Chemical and Biological Defense of the Russian Armed Forces, died as a result of an explosion in Moscow. His assistant Ilya P. also died on Tuesday, Baza Telegram channel reports.

The two Russian military officers were leaving the entrance of a house at around 6am when an improvised explosive device was set off.

The bomb was either attached to or embedded in a scooter, media report.

The capacity of this explosive device was about 200 grams of TNT, the emergency services reported.

The Investigative Committee of Russia has opened a criminal case regarding the incident.