Ukraine says its troops in Russia have progressed further and that they've now captured over a hundred Russian servicemen. It's the biggest foreign incursion into Russia since the Second World War, and today, saw the extraordinary sight of a Ukrainian war correspondence reporting from inside Russia. Ukraine's incursion began just over a week ago and took Moscow by complete surprise. Despite claims of territorial gains, Ukraine insists it's not interested in taking over Russian territory country. Russia claims it stopped any further advances. In a moment, we'll hear from our Russia editor, Steve Rosenberg, about how dangerous a moment this is for President Putin. But first, our Ukraine correspondent, James Waterhouse, joins us from the Sumi region on the border with Russia. James.

Rita, there is something strange going on in Ukraine. We're seeing President Zelensky go from describing difficult circumstances on the front line to having very choreographed public briefings. He's almost dictating proceedings to his terms for peace down the line, something Russia has done until this point, really, for the large part of its full-scale invasion. His logic is that this cross-border attack will bring peace closer. But, strangely, it feels further away because of the intense fighting that has broken out. Nevertheless, this operation is continuing to gain Western support, most recently from European allies.

No border checkpoint on this crossing to Russia, just a burnt-out Russian tank. A different assignment for Ukrainian war reporter Natalia Nahorna. This is a historic moment, she tells the camera in the city of Suja. Such a claim might be premature, but Ukraine is talking up this land grab while it can. It's providing humanity humanitarian aid and organizing evacuations. They are even plans to set up military offices. But on the battlefield, success always comes at a cost, as this injured soldier attests.

Fear, adrenaline. You realize when you enter their territory, how much we have suffered, how much our women and children have suffered, that now it's their turn.

The head of Ukraine's armed forces is having even more regular meetings with the President. Since the beginning of today, troops have advanced around one to two kilometers in some directions.

After the body blow of losing territory, Russia is now moving resources to try and take it back. As fighter bombers dropped glide bombs on Ukrainian forces on its own soil, Kyiv today claimed to have shot one of them down. The Su-34s are thought to be £30 million each. Kyiv is trying to change the politics of this war by shaking up the fighting itself. It's certainly done the latter. James Waterhouse, BBC News, Suomi region.

It feels like Ukraine's incursion is changing the equation and putting the Kremlin under pressure. A brief appearance today by President Putin, but no comment on the Ukrainian assault, which his troops are struggling to repel. The Russian military released these images, claiming to show it targeting Ukrainian troops in Kursk region. Moscow blames the West, too, for the incursion.

When they started in the United States, The main rule was, don't poke the bear. What the West is doing today, they are poking the bear.

The public's sense of shock is growing.

I feel incredible anxiety, Yulia says, as if my hands are tied because there is nothing I can do about this. It's frightening to see the images of people panicking, Tatyana says, of people being evacuated.

For some here, what is happening in Southern Russia is a wake-up call.

Over the last two and a half years, many Russians have tried not to notice what is happening, to get on with their lives, to pretend that there's no war. But with what's happening now in Southern Russia, not noticing is no longer an option.

Especially here in Kersk. It's the air raid siren, she says. Get inside fast. Ukrainians soldiers haven't reached this city, but no one here knows what lies ahead. Tens of thousands of Russians have fled the fighting in the border area. Some have taken refuge in Kyrsk. Vera left home in such a rush. She had no time to pack. I have nothing but the clothes on my back, she says. I'm looking for something warm. The Kremlin insists it will achieve its aims in this war. Russians are wondering when. Steve Rosenberg, BBC News, Moscow.

Well, this isn't the first incursion into Russia's territory by Ukraine since the war started in 2022, but it is the deepest most sustained so far. Bbc Verify's Olga Robinson has been looking at the latest footage emerging.

Here at BBC Verify, we have been analyzing satellite imagery and the latest footage as Ukraine continues to push further into Russian territory. Here's the latest assessment from the Institute for the Study of War, a US-based think tank. And you can see here on this map just how far Ukrainian troops have reportedly advanced into Russia over the past week. The furthest we have observed Ukrainian troops within the Kursk region is here, more than 28 kilometers, that's 17 miles from the border. Using satellite imagery, we have also been able to identify five locations where Russia appears to be rapidly digging a network of train lines. And we know these are new because the structures only began to appear in the days after Ukraine crossed into the Kursk region last Tuesday. For instance, take a look at this satellite imagery from the day when the incursion started compared with this one that was taken on the 14th of August. You can clearly see here, these structures were only built over the past week. We have also geolocated this video that shows the construction of one of these trenches. You can see here the heavy machinery next to a long stretch of piled earth near a road not far from the Korsk nuclear power plant.

Matthew Savill, a military expert with the UK-based Russie think tank, told us that the fact that the Russians are Building these trenches suggests they are concerned about further Ukrainian advances. And so far, Ukrainian troops are still miles away from those trenches. But our team will continue to monitor for any advancements.

That was Olga Robinson. Well, let's join our Russia editor, Steve Rosenberg, again from Moscow. Steve, we've seen their part of the response from Russia, but what could Vladimir Putin do next?

Well, I'll tell you what he won't be doing next week, and that is picking up the phone and calling Kyiv about this. Senior Russian officials today said that they were putting on hold the whole idea of peace talks, not that any serious negotiation had been scheduled. No, Vladimir Putin made clear earlier this week what his Our priority is to push the enemy out of Russian territory, he said, and he will throw resources at that in order to achieve that. Although what he won't want to do is to have to redirect Russian soldiers from Eastern Ukraine. But I just want to share something that happened early this morning. I was walking past the Kremlin, and there were some workers there setting up for a concert or a festival or something. And suddenly on a large video screen, the Edith Piaf classic, Non, je ne regret rien. No, I regret nothing, started playing and echoed across Red Square. It was a really surreal moment, and it made me think that Vladimir Putin shows no sign of regret for his decision to invade Ukraine, even though this war has now come to Russia.