MOSCOW, December 17. /TASS/. Lieutenant-General Igor Kirillov, the head of Russia’s Radiation, Chemical and Biological Defense Forces, who was killed in a terrorist attack in Moscow on Tuesday morning, knew that he was being "hunted," his efforts to expose the Western clandestine biological laboratories being the reason, the governor of the Kostroma Region, Sergey Sitnikov, said on his Telegram channel.

"Some time ago he (Kirillov - TASS) told me that he had already been warned that the hunt for him was on. No doubt, the reason was his spearheading efforts to expose secret biological laboratories, including those in Ukraine. There was a clear understanding that the combat personnel he had trained and the combat efforts by his troops were a powerful weapon. And this did not escape the attention and malice of our enemies," Sitnikov wrote.

Kirillov was born in Kostroma and received his higher military education there. He is an honorary citizen of the Kostroma Region. From September 2014 to April 2017, he served as head of the Marshal Timoshenko Military Academy of the Russian Chemical Defense Forces in Kostroma.

"I particularly admired his work when he became the head of the Radiation, Chemical and Biological Protection Academy. The academy was not in the best shape at that time. For several years, admission and graduation rates at the academy had been falling. In a very short time Kirillov managed to right the ship at the academy. Alongside growing admission and excellent academic performance fundamental research in the military-technical field began," Sitnikov said.

The Kostroma governor described Kirillov as his comrade and friend.

"I have no doubt that every effort will be made to solve this crime. I have no doubt that those who plotted and carried out the attack will be brought to justice. I offer deep condolences to his wife Svetlana, to his sons, all his family, relatives and friends," Sitnikov said.

On the morning of December 17, an explosive device was set off on Ryazansky Avenue in Moscow. It had been planted in a scooter parked near the entrance of an apartment building. Kirillov and his assistant were killed. Russia’s Investigative Committee opened a criminal case under Articles 105, 205 and 222 of the Criminal Code (murder, terrorist act, illegal trafficking of weapons and ammunition). Detective activities are currently underway to identify the persons involved.