More than 51,000 households were left without gas and 1,500 apartment buildings had no winter heat in Moldova's pro-Russian separatist enclave, authorities said on Monday, as Moldova and Russia traded blame for an escalating energy crisis.

A renegade part of Moldova once boasted it would become a Russian-speaking Switzerland. Now without gas, its leader assured residents, “We will not allow a societal collapse.”

The head of Moldova’s breakaway region Transnistria has urged residents to burn firewood for heating and warned that blackouts cannot be avoided, after Moscow stopped supplying gas via Ukraine.

The Russian troops have also been using electric scooters, motorcycles and ATVs, which allow them to disperse quickly across the front, a Ukrainian official told The Times. The stepped-up attacks have heightened longstanding concerns over how Ukraine manages its military and have countered assumptions that Moscow’s offensive would slow.

Russia said Monday that its forces had captured the "important logistics hub" of Kurakhove in eastern Ukraine in what would be a key advance after months of steady gains in the area. It called the town "an important logistics hub" and said its capture would allow Russian forces to seize the rest of the Donetsk region "at an accelerated pace".

The claim, which drew no response from Ukrainian authorities, came a day after the Russian Defense Ministry said Ukrainian forces had launched a new thrust in Russia’s Kursk border region.