- Ukrainian forces advanced at least 6 miles into Russia's Kursk region in a surprise attack.
- Ukraine has not commented on the attack and many details remain unclear.
A Ukrainian incursion into Russian territory over the last two days appears to have caught Moscow unprepared, according to multiple reports.
Locals in the Kursk region rushed to evacuate without state support, and Russian military bloggers have angrily asked why Russian forces were not more ready.
Meanwhile, the Kremlin offered contradictory information about what is happening, suggesting disarray at the top.
The exact scale of the incursion is still unknown. An analysis by the Institute for the Study of War said Ukrainian armored vehicles pushed at least 6 miles into Kursk, which borders northern Ukraine.
Russian officials said that as of Tuesday, Ukraine had sent up to 1,000 troops into the fight, backed by 11 tanks and 20 armored combat vehicles. Footage shared by Russian military bloggers suggests that at least two Ukrainian brigades are involved.
As of Thursday, the ISW assessed that Ukrainian forces had passed two defensive lines.
Ukraine has not commented on the operation, and Business Insider could not independently confirm the details.
Russia has offered mixed accounts of what is happening — Alexey Smirnov declared the situation under control on Wednesday, as President Vladimir Putin convened an emergency meeting with his security chiefs.
"It appears that yet again, in the past few days, the Ukrainians have surprised Russia, and observers in the West, with their latest operation," wrote Mick Ryan, a war analyst and retired major general, in a recent analysis.
He noted that "the Ukrainians have attacked with a highly mobile, mechanised force," strongly supported with air defense.
Russia declared a state of emergency in the region. It began an evacuation of the region's border towns, according to state-controlled media.
But one resident in Sudzha — a major focus of the Ukrainian attack — told the independent Russian outlet Meduza that she had fled already, hours before any evacuation was offered.
On Tuesday, they had been "awoken at 3 a.m. by the sound of the missiles being launched at us," she told the outlet.
Kursk Nuclear Power Plant also appears to have been thinly protected, with Russia only belatedly moving air defense units into the area, the Kyiv Post reported, citing the independent Russian outlet iStories.
Several Russian military bloggers excoriated the Kremlin for what they see as a failure to prepare or respond effectively, according to the ISW.
The influential pro-Kremlin account Rybar wrote on Wednesday that Russia's military top brass had been monitoring a Ukrainian buildup for the past two months, but did little to prepare.
Early on Wednesday, Russian security council chair Dmitry Medvedev wrote in a Telegram post that serious lessons needed to be learned.
On Wednesday, White House Press Secretary Karine Jean-Pierre suggested that the US also had limited knowledge, saying "we're going to reach out to the Ukrainian military to learn more about their objectives."