Russian shelling hit more civilian targets in Ukraine, starting a fire at a town’s hospital and damaging five apartment buildings, local officials said Tuesday, as Ukrainian authorities reported a Moscow troop buildup in eastern areas before what Kyiv suspected was an impending new offensive by Russia around the anniversary of its invasion.

A hospital in the northeastern town of Vovchansk caught fire late Monday as a result of the shelling, regional Ukrainian emergency services reported.

The shelling caused multiple fires in the town, including at its two-story municipal hospital, the State Emergency Service in the northeastern Kharkiv region said in an online statement.

Emergency crews evacuated eight civilians from the site before putting out the blaze, which caused no casualties, authorities said.

Vovchansk is in the Kharkiv region, which was occupied by Russia after its full-scale invasion began on Feb. 24 and subsequently retaken by Ukraine during a counteroffensive last year.

The anticipated Russian push may seek to recapture territory Moscow lost in that counteroffensive.

Ukrainian officials say they expect the new drive to come in eastern and southern Ukraine, as the Kremlin strives to secure areas it has illegally annexed and where it claims its rule is welcomed.

Russian forces are “regrouping” as they attempt to break Ukrainian lines in five areas in the country’s east and northeast, the Ukrainian military reported Tuesday.

The General Staff of the Armed Forces of Ukraine said Moscow was focusing its efforts near the towns of Lyman, Bakhmut, Avdiivka and Novopavlivka in the eastern Donetsk region, as well as Kupiansk in the Kharkiv province.

In the Donetsk region, Russian forces also kept up their shelling of Vuhledar, a mining town that has been one of Moscow’s key targets, the Ukrainian presidential office said. Five apartment buildings were destroyed in the town, the office said, which had a prewar population of 14,000.

Donetsk province has seen a marked influx of Russian troops in the past few days, according to regional Gov. Pavlo Kyrylenko.

“The transfer of Russian army units goes on day and night. (Russian) shelling intensifies, pressure from the Russians intensifies each day,” Kyrylenko said on Ukrainian television.

Russia is also preparing for a major offensive in the eastern Luhansk region, directly north of Donetsk, local Gov. Serhii Haidai said in televised remarks.

The number of Russian attacks in the province increased “dramatically” on Monday and overnight, he said.

“The occupiers are looking for weak points and have brought a lot of equipment and thousands of troops to the front line,” Haidai said.

A dozen towns and villages in the northeastern Kharkiv region also came under Russian shelling in the past 24 hours, the presidential office said.

U.N. Secretary-General António Guterres expressed concern about an uptick in fighting as the winter draws to a close.

Peace prospects “keep diminishing” and “the chances of further escalation and bloodshed keep growing,” he said in a speech late Monday.

Battlefield setbacks have embarrassed the Kremlin, and Russian President Vladimir Putin is keen to cement public support for the war. Ensuring Kremlin rule in the eastern Donbas industrial region, bordering Russia, is expected to be a key objective.

Analysts Skeptical of Russia’s Capabilities

Some military analysts are skeptical, however, about Russia’s ability to mount a large new offensive in coming weeks. Ukraine and Russia are both still training their new troops and amassing weapons.

The U.K. Ministry of Defense said in an assessment Tuesday that Russia is “requiring undermanned, inexperienced units to achieve unrealistic objectives due to political and professional pressure.”

“Russian leaders will likely continue to demand sweeping advances,” it added. “It remains unlikely that Russia can build up the forces needed to substantially affect the outcome of the war within the coming weeks.”

Michael Kofman, an American military analyst and director of Russia Studies at the CAN, a research organization in Arlington, Virginia, tweeted on Monday it was unclear how big an offensive Russia is able to mount.

He added, “but I suspect it may prove underwhelming, focused largely on the Donbas.”

Meanwhile, the shelling kept Ukraine’s civilian population under pressure in some areas of the country.

Russia launched six missile and two dozen air attacks as well as 75 shelling incidents hitting civilian targets in Kharkiv, Donetsk, Dnipropetrovsk and Kherson, over the past 24 hours, the General Staff of the Ukrainian Armed Forces said in a statement Tuesday.

About 60,000 households in Marhanets were left without water after Russian shelling near the Zaporizhzhia nuclear power plant cut the power supply to a local pumping station, authorities reported.

Mykola Lukashuk, who heads the Dnipropetrovsk Regional Council, accused Russian forces of firing on towns and villages neighboring the plant, Europe’s largest, with heavy artillery and multiple rocket-launchers overnight.