The footage claims to show an Australian man captured by Russian forces while fighting for Ukraine. As officials in Canberra scramble to verify its authenticity, the case has sparked questions about the risks faced by foreign volunteers in the conflict.

Officials are scrambling to provide support for an Australian citizen reportedly being held hostage by pro-Russian forces in Ukraine.

"Whoever, and however much they try to destroy, they will face many times more destruction themselves and will regret what they are trying to do in our country," Putin said on Dec. 22.

Russia's Kazan city was targeted by a major drone attack from Ukraine on Saturday. The attack damaged a high-rise apartment building but did not cause any casualties. Tatarstan's leader Rustam Minnikhanov confirmed the attack on Telegram saying that "today Kazan suffered a massive drone attack.