Russian authorities said they were probing the attack as "terrorism"
From
To
Igor Kirillov was killed when a explosive device attached to a scooter went off outside an apartment building
Ukraine claimed responsibility for the attack
The blast shattered several windows of the building and severely damaged the front door
Investigators attend site of Moscow blast that killed senior Russian army official
The head of the Russian army's chemical weapons division was killed Tuesday in a brazen Moscow attack claimed by Kyiv, the most senior militar…