Moscow on Saturday mounted a "counter-terror operation" in three border regions adjoining Ukraine to halt Kyiv's biggest cross-border offensive in the two-and-a-half-year conflict. Ukrainian units stormed across the border into Russia's western Kursk region on Tuesday morning in a shock attack and have advanced several kilometres, according to independent analysts. Russia's army has rushed in extra troops and equipment, including convoys of tanks, rocket launchers and aviation units -- though neither side has given precise details on the extent of the forces they have committed.

At least 3,000 civilians have been evacuated from Russian border areas, where emergency aid and medical supplies have been ferried in, while extra trains to the capital Moscow have been put on for people looking to flee. "The war has come to us," one woman who fled the border zone told AFP at a Moscow train station on Friday, declining to give her name. Russia's army said Ukraine initially despatched around 1,000 troops, and more than two dozen armoured combat vehicles and tanks -- but it has since claimed to have destroyed around five times as many pieces of military hardware.

AFP could not verify those numbers and both sides have repeatedly been accused of inflating the number of enemy losses while downplaying their own setbacks. Russia's national anti-terrorism committee said late Friday it was starting "counter-terror operations in the Belgorod, Bryansk and Kursk regions ..

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