Russia launched a barrage of ⁠drone strikes on Ukraine's energy infrastructure overnight on Monday, cutting off power in five regions across the country amid freezing temperatures and high demand, Ukrainian officials said.

The Ukrainian air force said that Russian troops had launched 145 drones. Air defense units shot ‍down 126 of them, it said.

"As of this morning, consumers in ‍Sumy, Odesa, Dnipropetrovsk, Kharkiv, and Chernihiv regions are without power," the energy ministry said in a statement. "Emergency repair work is underway ⁠if the security situation allows."

In the southern Odesa region, energy and gas infrastructure was damaged, the regional governor said, adding that one person was ​hurt in the attack.

DTEK, Ukraine's largest private energy company, said its energy facility in Odesa was "substantially" damaged, knocking out power for 30,800 households.

A local power grid company in northern ‍Chernihiv region said that five important energy facilities were damaged, leaving tens of thousands of ⁠consumers without power.

Russia also hit Ukraine's second-largest city of Kharkiv with missiles on Monday morning, significantly damaging a critical infrastructure facility, Mayor Ihor Terekhov said.

Moscow has stepped up a winter campaign of strikes on the Ukrainian energy system, including generation, electricity transmission ⁠and gas production facilities, amid ​freezing temperatures that complicate repair ⁠works.

The attacks have caused long blackouts.

"Being without electricity for more than 16 hours is awful," Serhii ‍Kovalenko, CEO of energy distribution company Yasno, said on Facebook late on Sunday. "And it's not because of the ‌energy companies, but because of cynical attacks by the enemy, who is trying to create a humanitarian disaster."

Ukraine declared an energy emergency last week as its grid ⁠crumbled ​due to accumulated wartime ‍damage and a new targeted wave of Russian bombardments.

Energy Minister Denys Shmyhal said on Monday the government would implement projects to improve ‍electricity transmission from the western part of the country to its power-hungry east.