Battles rage in Russia as Kremlin struggles to repel surprise Ukraine incursion

A convoy of burnt-out military trucks, some bearing the "Z" symbol of the Kremlin’s war and appearing to contain bodies, sits along the side of a highway.

But the video, circulating on social media Friday and geolocated by NBC News, doesn’t show a beleaguered section of the front lines in eastern Ukraine. It is a village in Kursk, across the border in southern Russia.

For days now, Vladimir Putin’s forces have struggled to put down an incursion into Russian territory by Ukrainian troops, a surprise attack that threatens to upend the war’s status quo and open a new front in a daring challenge to the Kremlin.

The unprecedented assault entered its fourth day Friday with battles still raging and Moscow rushing reinforcements and bombing its own territory to try to contain the Ukrainian advance.

The operation has left observers struggling to track fast-moving developments on the ground — and to figure out Kyiv’s strategy in launching the attack while its forces are still struggling in several of the conflict’s longtime flashpoints.

With Ukraine tightlipped and Russian officials offering little detail on the extent of the Ukrainian advance, it’s hard to judge the scale or success of the operation beyond poring over videos, like the one showing the convoy and relying on the frenzied chatter of Russia’s influential and often-furious military bloggers.

Still, it seemed clear this was no mere headline-grabbing raid, the likes of which have been conducted by anti-Kremlin Russian militias since last year, but a carefully planned operation, military analysts have said.

“If we take a step back, it looks to me like the first time that Ukraine’s state forces have invaded Russia,” Frank Ledwidge, a former British military intelligence officer and senior lecturer in war studies at England’s University of Portsmouth, told NBC News. “That’s very significant.”

Russia’s defense ministry has boasted that Ukrainian troops had been stopped, but has yet to report pushing Kyiv’s forces back across the border.

Military command said that some 1,000 Ukrainian soldiers, backed by tanks and military vehicles, were involved in the initial attack. Federal authorities have declared a state of national emergency and thousands of people have been evacuated from Kursk amid reports of civilian casualties and destruction.

On Friday, the ministry said it was sending new reinforcements to the area. It shared videos showing columns of heavy armor headed toward Kursk, and Russian jets bombing what it said were Ukrainian troops and equipment on Russian territory.

But Russian military bloggers painted a less rosy picture, reporting that Ukrainian forces could be in at least partial control of the border town of Sudzha, home to an important natural gas transit hub, and may have moved miles into Russian territory. Some are sounding irate about Russia’s response and why it has been caught off guard.

The Institute for the Study of War said Thursday that Ukraine was able to achieve “operational surprise” and its forces could have moved as deep as 20 miles into Russia although, it said, they “most certainly do not control all of the territory.”

NBC News has not verified the reports.

Ukraine has stayed largely mute on the incursion.

In a first public acknowledgement, presidential adviser Mykhailo Podolyak on Thursday blamed “Russia’s unequivocal aggression” for any escalation within its own territory. President Volodymyr Zelenskyy has not referred to the incursion directly, only saying in his overnight address that “Russia brought war to our land and must feel what it has done.”

The surprise assault into Russia at a time when Ukraine’s overstretched forces have been struggling to hold onto their own key territory has surprised many observers.

“At a time when Ukrainian defenders in the east are being pushed back on several axes, the use of highly capable Ukrainian combat forces in Kursk is either a brilliant countermove to shift the momentum in the war, or a strategic error which compounds the challenges in Ukraine’s eastern Ukraine defensive operations,” Mick Ryan, a senior fellow for military studies at Lowy Institute, an Australian-based think tank, wrote on X.

Analysts have suggested other possible motives for the operation, including recapturing the world’s attention, a desire to present a victory to a domestic audience or even grabbing as much enemy territory as possible to use as a bargaining chip in future peace talks.

For Ledwidge, with the University of Portsmouth, the most plausible theory is that Ukraine sent its own troops into Kursk “to get the jump” on Russian forces who may have been planning a new offensive on the Sumy region, just across the border. Russia launched an offensive in the neighboring Kharkiv region in May, and Ukrainian officials have warned that Russia could attack Sumy next.

“So the idea is that Ukrainians just stole a march on them,” Ledwidge said.

This hypothesis appears more likely than an effort to draw forces away in the east, he said, because the wealth of Russia’s resources means that unlike the Ukrainians they would not necessarily have to move troops and weapons from one front to defend another.

There are also questions about what the incursion might mean for the support Ukraine relies on from its Western allies.

State Department spokesman Matthew Miller has said the U.S. was not in on Ukraine’s plans.

Despite concerns that the use of U.S.-supplied weapons in the cross-border assault could spark backlash, Washington signaled Thursday that it had no issues and saw the operation as an effort by Kyiv to protect itself. “It is consistent with our policy,” deputy Pentagon press secretary Sabrina Singh said at a news briefing.

This article was originally published on NBCNews.com