Russian drones struck apartment buildings and energy facilities in the southern Ukrainian city of Odesa overnight, injuring six people including three children, officials said Wednesday.

Russian President Vladimir Putin expressed confidence in his country's eventual victory in the nearly four-year war against its neighbor.

Four apartment buildings were damaged in the Odesa bombardment, according to regional military administration head Oleh Kiper. The DTEK power provider said two of its energy facilities had significant damage. The company said 10 substations that distribute electricity in the region have been damaged in December.

Russia has escalated attacks on urban areas of Ukraine. As its invasion approaches a four-year milestone in February, it has also intensified targeting of energy infrastructure, seeking to deny Ukrainians heat and running water in the bitter winter months.

Between January and November, more than 2,300 Ukrainian civilians were killed and more than 11,000 were injured, the United Nations said earlier in December. That was 26% higher than in the same period in 2024 and 70% higher than in 2023, it said.