VIDEO: The Moment The Russian Chemical Weapons Chief Is Blown Up In Moscow

Shocking video purportedly shows the bombing that killed Lt. Gen. Igor Kirilov, the head of Russia's Radiation, Chemical and Biological Defence Troops on the streets of Moscow.

The video, which appears to be taken from inside a vehicle, shows two men walking out of a building at night onto a snowy street.

Seconds later a large blast fills the screen.

The explosive device was attached to a scooter, officials said.

The blast shattered several windows of the building and severely damaged the front door, according to an AFP reporter on the scene.

Kirillov was killed along with his deputy.

A Ukrainian official said the Ukraine's security service was behind the attack, the Associated Press reported.

"An unprecedented crime committed in Moscow", the Kommersant daily said on its website.

Kirillov, 54, was under sanctions from several Western countries for actions carried out in the war against Ukraine, including the alleged use of chemical weapons.

Tuesday's blast came a day after Russian President Vladimir Putin said that his troops had the upper hand across the frontline in Ukraine.

Both Moscow and Kyiv are seeking to improve their position on the battlefield before US President-elect Donald Trump comes to power in January. Trump has vowed to end the conflict.