Ukraine’s rapid advance into Kursk startled Russia and revealed its weaknesses.

Kyiv: A daring Ukrainian military push into Russia’s Kursk region has seen Kyiv’s forces seize scores of villages, take hundreds of prisoners and force the evacuation of tens of thousands of civilians in what has become the largest attack on the country since World War II.

In more than a week of fighting, Russian troops are still struggling to drive out the invaders.

Russia’s regions of Kursk, Bryansk and Belgorod share a 1,160-kilometer (720-mile) border with Ukraine. That includes a 245-kilometer (152-mile) section in the Kursk region. This frontier had only symbolic protection before Moscow invaded Ukraine in 2022. It’s been reinforced since then with checkpoints on key roads and field fortifications in places, but building solid defenses has remained a daunting task.

The most capable Russian units are fighting in eastern Ukraine, where they have been pressing offensives in several sectors, with incremental but steady gains. Moscow has used the regions to launch airstrikes and missile attacks on Ukrainian territory but doesn’t have enough land forces there.

Because of the porous border and manpower shortages, there have been earlier forays into the Belgorod and Bryansk by shadowy groups of pro-Kyiv commandos fighting alongside Ukrainian forces before they pulled back.