Russia says its forces have pushed deeper into the eastern Ukrainian town of Pokrovsk, with video on Tuesday showing Russian soldiers moving into the town on motorbikes and on the roofs of battered cars and vans amid thick fog.
Ukraine's top military commander, Oleksandr Syrsky, estimated that Russia is massing about 150,000 troops in its bid to capture Pokrovsk. He said Ukrainian forces are seeking to remove about 300 Russians who Kiev says have so far infiltrated the town.
"Reuters" presents the most important information about Pokrovsk, which Russians call by its Soviet-era name Krasnoarmeysk, and the long battle for control that began in earnest in mid-2024.
Pokrovsk is a road and rail hub in eastern Donetsk Oblast of Ukraine with a population of about 60,000 before the war. It was previously an important logistics center for the Ukrainian army, located on a key route that troops used to supply other fortified posts along the front line.
However, most people have already fled, all children have been evacuated, and few civilians remain among the destroyed apartment buildings and crater-strewn roads of Pokrovsk.
Ukraine's only mine producing coking coal - used in the once-vast steel industry - is located about 10 km west of Pokrovsk. Mining operations there have been suspended.
Pokrovsk is also home to the largest technical university in the region, which is now abandoned, damaged by shelling.
Russia wants to seize all of Donbas, which encompasses the Luhansk and Donetsk regions. Ukraine still controls about 10% of Donbas - an area of about 5,000 square kilometers mostly in the northern part of Donetsk.
Capturing Pokrovsk and Konstantinovka in the northeast, which Russian forces are also trying to besiege, would give Moscow a platform for an offensive northward toward the two largest remaining Ukrainian-controlled cities in Donetsk - Kramatorsk and Slavyansk.
It would also leave Ukraine's Dnipropetrovsk region in the west, where Russian forces say they have already established a foothold, more vulnerable to Russian advances.
Pokrovsk would be Moscow's most significant single territorial acquisition in Ukraine since it captured the devastated town of Avdiivka in early 2024.
Moscow wants to convince the West that the capture of the rest of Donetsk Oblast is inevitable and that it would be better for Kiev to voluntarily surrender it as part of a peaceful agreement.
Ukraine, which rejects the idea, is eager to show its Western partners that it can make the Russians pay a high price for relatively modest territorial gains and therefore deserves continued military and financial aid.
Russian President Vladimir Putin has said that Donbass is now legally part of Russia. Kiev and most Western countries reject Moscow’s seizure of the territory as an illegal land grab.
Some Western military analysts, such as Rob Lee, a senior fellow at the U.S.-based Foreign Policy Institute, say that taking Pokrovsk would be an important victory for Russia for operational reasons.
But Russia will still fall short of its goal of controlling the rest of Donetsk, including the two fortress cities of Kramatorsk and Slavyansk, Lee noted.
Russia has been threatening Pokrovsk for more than a year. Instead of the frontal attacks it used in earlier battles, such as the bloody campaign for the similarly sized city of Bakhmut, the Russian army has used evasive maneuvers to gradually encircle Pokrovsk and threaten Ukrainian supply lines.
Russian forces have been harassing Ukrainian troops, sending in small units and drones to disrupt logistics and sow chaos before sending in larger reinforcements.
Ukraine claims the Russian offensive has resulted in heavy losses for its forces. Moscow argues that it is Ukraine, with its much smaller population, that is at risk of being left without people, and that its own slower tactics are designed to minimize casualties.
A Ukrainian incursion into Russia’s Kursk region last year, which Moscow repelled, slowed the Russian attack on Pokrovsk.
Ukraine has rushed to reinforce its positions in the town.
Ukrainian President Volodymyr Zelensky said on Tuesday that bad weather was facilitating Russian attacks, which he said were increasing in scale.
Separately, the Ukrainian military said Moscow had stepped up efforts to bring in more troops in the past few days, using thick fog as cover.
"Their goal remains unchanged - to reach the northern borders of Pokrovsk and then try to surround the agglomeration", the 7th Parachute Corps of Ukraine said on Facebook.
DeepState, a Ukrainian project that maps the front line based on verified open-source imagery, shows Russian forces invading the city from the south, although much of it remains a gray area, outside the firm control of either side.