Technicians in Ukraine's capital Kyiv worked tirelessly to restore power on Tuesday after Russia's latest wave of missile strikes caused more power disruption.
As temperatures plummet across the country, nearly half of Ukraine's energy system has already been damaged after months of strikes on power infrastructure. Many residents are left in the cold and dark for hours at a time as outdoor temperatures drop below freezing.
Meanwhile, video footage posted on social media showed a large explosion following a drone attack which set an oil storage tank on fire at an airfield in the Russian territory of Kursk.
The attack came a day after Ukraine appeared to launch attacks on two military airfields deep inside Russia in a bid to disrupt the Kremlin's strategy of trying to cripple the Ukrainian electrical grid.
But the US says it's not encouraging Ukraine to strike beyond its borders.
"We have not provided Ukraine with weapons that it is to use inside of Russia, we've been very clear that these are defensive supplies. We are, the president said very clearly some time ago, we are not enabling Ukraine to strike beyond its borders," says US State Department spokesperson Ned Price.
In Moscow, Russian President Vladimir Putin reportedly raised the attacks during a meeting on Russia's domestic defences with his security council.
The Kremlin says the strikes were conducted using Soviet-era drones. Kyiv has not directly claimed responsibility for the strikes but has celebrated them.
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