Ukraine is continuing it cross-border incursion into Russia for a fourth day.

Here's what's been happening:

• Reports suggest that Ukrainian troops are operating more than 10km (six miles) inside Russian territory – the deepest cross-border advance by Kyiv since Moscow launched its full-scale invasion in February 2022
• Moscow says it is moving reinforcements – including heavy armoury and missile launchers – to the western Kursk region, state media reports
• Russia's defence ministry says its troops are "continuing to repel" Ukraine's incursion - a claim not verified independently
• Its emergency ministry declared a federal state of emergency in the area
• President Vladimir Putin has chaired a meeting with members of the Russian Security Council at a residence outside of Moscow
• Ukraine has not explicitly confirmed the incursion, but President Volodymyr Zelensky says Moscow must "feel" the consequences for its invasion
• In Ukraine, the prosecutor general's office say a Russian strike on a supermarket in the front-line Donetsk region has killed 14 people and left 44 injured

We're pausing our live coverage now, but you can see the latest on War in Ukraine section of the BBC News website.

The death toll has now risen to 14 in what Kyiv says was a Russian artillery strike on a supermarket and a post office in Ukraine's eastern city of Kostyantynivka.

The new figure was given by Ukraine's prosecutor general's office.

It adds that 43 people were injured.

Russia has not publicly commented on the attack.

Image source, EPA

This July was the deadliest month for Ukraine's civilians since October 2022, the UN's human rights monitoring mission in Ukraine says.

"Coordinated attacks launched by the Russian armed forces across Ukraine on 8 July which killed dozens of people during a single day made last month exceptionally deadly," the body says in a statement.

The high number of casualties last month "continued an alarming trend of increasing civilian casualties since March", it says.

In its monthly update on civilian harm, it says it's verified that conflict-related violence killed at least 219 civilians and injured 1,018 in July.

Lana Lam
Live reporter

Is it definitely Ukraine behind the recent surprise incursion into Ukraine's Kursk region?

“We can say with certainty that this is Ukraine,” the BBC's Ukraine correspondent, James Waterhouse, tells the latest episode of Ukrainecast from Kyiv. The attack marks “an incredibly significant time in this full-scale invasion”.

I'm listening in on the recording of today's podcast, presented by Lucy Hockings and Vitaly Shevchenko, who, along with James, have been discussing the offensive.

Continuing, James tells us pro-Ukrainian Russian militants have previously carried out smaller attacks, “but this [attack] involves a regular force in big numbers with armoured vehicles to boot and accompanying airstrikes”.

Does this latest development mark a new chapter in the Ukraine war? And how to will the incursion impact Russian sentiment around the conflict?

All of this and more will be answered in today's Ukrainecast episode, available this evening.

Ukraine and Russia have a long, complicated history.

Ukraine became independent in 1991, following the fall of the USSR, and gradually grew closer to the European Union and the West.

Russia had long resisted Ukraine's move towards the EU and the West's defensive military alliance, Nato.

For years, Putin denied Ukraine‘s statehood, culminating in a lengthy 2021 essay saying that Russians and Ukrainians were one people - a claim rejected as false by many historians in Ukraine and around the world.

He frequently - and falsely - accused Ukraine of being taken over by extremists, ever since its pro-Russian president, Viktor Yanukovych, was ousted in 2014 after months of protests against his rule.

At that time, Russia retaliated by seizing the southern Ukrainian region of Crimea. A revolt in the east by Russia-backed separatists sparked a war that claimed some 14,000 lives.

Image source, Getty Images

In 2021, Putin began deploying large numbers of Russian troops close to Ukraine's borders. But for months he denied he would invade his neighbour.

Announcing the invasion on 24 February 2022, Putin accused Nato of threatening Russia’s “historic future as a nation" - a claim rejected as groundless by the military alliance.

The US had warned its European partners that military manoeuvres on Russia's borders were consistent with preparations for an attack on Ukraine but, until that day in 2022, few believed Russia would genuinely launch an invasion.

Yet, perhaps just as few thought Ukraine would be able to hold out for as long as it has.

The official death toll from a Russian strike on a supermarket in eastern Ukraine has been revised upwards.

The latest update from Ukraine’s interior ministry says that 12 people were killed and 44 were injured – emergency services continue to work at the site.

As we've been reporting, the attack took place in the city of Kostyantynivka in the eastern Donetsk region.

There are still many unknowns about the Kursk region incursion, including how many troops are involved and how much territory Ukraine has managed to secure.

Shashank Joshi, defence editor of the Economist magazine, says Russia has estimated about 1,000 troops were involved, and on the Ukrainian side, about two to four brigades may be involved - he adds this is unlikely to be thousands of troops.

It's now day four of that incursion, but Joshi tells BBC Radio 4's World at One that Ukraine "could keep this up for weeks".

But one of the challenges is how Ukraine supplies its forces deep inside Russia with the American and European armour its been using.

"Supply is one of the big, big questions right now and on the Russian side it's how many of their reserves they'll move to this area to counteract the assault," he says.

On the idea that Ukraine is trying to draw troops away from other fronts on the battlefield, Joshi says he hasn't seen evidence that forces in Ukraine's eastern Donbas have been sent to Kursk.

Image source, Reuters

President Vladimir Putin has been chairing a meeting with members of the Russian Security Council at a residence outside of Moscow.

The head of the council, Sergei Shoigu, and Russian defence minister Andrei Belousov are among those seen attending.

It's not clear precisely what the meeting has been focusing on, but the topic is reportedly fighting terrorism.

Putin's foreign ministry spokesperson has previously referred to the Ukrainian incursion as "terrorist".

Image source, Reuters

The Institute for the Study of War has produced an estimate for the extent of Ukraine's incursion into the Kursk region of Russia – you can see a visualisation below:

Verified video shows destruction after supermarket strikepublished at 15:02 British Summer Time 9 August

15:02 BST 9 August

By Richard Irvine-Brown

BBC Verify has also verified a video and stills of the aftermath of a strike on a supermarket and post office in Kostyantynivka, Donestk Oblast, Ukraine.

The video and stills from Kostyantynivka show a supermarket and post office on fire, with people struggling to help.

The damage is at this point 48.508837, 37.674597 on the western side of the town, and, again by the weather and the direction of shadows, the images were taken around 11:00 local time.

While this location is 160km (99 miles) from the border with Russia, the town is only 20km (12 miles) from Russian-held Kurdiumivka to the east.

Footage posted online shows heavily damaged Russian convoypublished at 14:51 British Summer Time 9 August

14:51 BST 9 August

By Richard Irvine-Brown

BBC Verify has examined two videos of separate events on either side of the Ukraine-Russia border, following Ukraine’s military incursion into Russia’s Kursk region.

We have verified a video of a 15-vehicle Russian convoy, damaged, burned and abandoned in the Kursk region, western Russia.

The convoy video was filmed around 06:00 local time, as seen from the direction and length of the shadows, and first appeared online this morning. The weather is also a match for early morning over the town.

The footage also shows Russian soldiers, some injured, possibly dead among the vehicles. It was filmed along the E38 road through the town of Oktyabr'skoe, roughly 38km (24 miles) from Russian's southern border with Ukraine.

The video has not been sent to the BBC directly, but it has been shared widely on social media and the Telegram messaging app.

The uploader of the video has been detained.

Image source, Reuters

If you're just joining us, here are the main developments from the past few hours as Ukraine continues for the fourth day its cross-border offensive in Russia's Kursk region:

• Moscow says it is moving reinforcements - including heavy armoury and missile launchers - to the western Kursk region, state media reports

• Russia's defence ministry says its troops are "continuing to repel" Ukraine's incursion - a claim not verified independently

• Ukrainian troops are said to be operating more than 10km (six miles) inside Russian territory - the deepest cross-border advance by Kyiv since Moscow launched its full-scale invasion in 2022

• Ukraine has not openly admitted the incursion, but President Volodymyr Zelensky says Moscow must "feel" the consequences for its invasion

• Ukrainian police say at least 11 people have been killed and 37 injured in a strike on a supermarket in the front-line Donetsk region
• Ukraine's military says it carried out an overnight strike on a military airfield deep in Russia, destroying gliding bombs stored at warehouses

Stay with us, as we'll be bringing all the latest news and analysis.

The death toll from a Russian artillery strike on a supermarket in the eastern Ukrainian city of Kostyantynivka has now risen to 11, Ukrainian police say.

They say another 37 people were injured, and there may still be a number of those trapped under the rubble.

Ukraine's cross-border surprise attack on Russia's Kursk region has entered its fourth day.

Watch below as the BBC's Russia editor, Steve Rosenberg, describes how in Moscow there has been a "sort of begrudging recognition" that the Ukrainian incursion has been "pretty successful so far":

As we reported earlier, the Ukrainian cross-border incursion into the western Kursk region in Russia is now in its fourth day.

Here we can see the aftermath of the incursion in the town of Sudzha, with images taken yesterday showing houses on fire and severely damaged buildings:

Image source, Reuters

Image source, Reuters

Image source, Reuters

Image source, Reuters

Steve Rosenberg
BBC Russia editor

Image source, IZ.RU/Reuters

The assault by Ukrainian forces on Kursk region and the fierce fighting there are a sign that hostilities are coming closer to home. But will that turn Russian public opinion against the war?

Not necessarily.

Last year I visited Belgorod, a Russian region which, like Kursk, borders Ukraine. It was being shelled from across the border. Everyone I met told me that nothing like this had happened before Russia’s full-scale invasion of Ukraine: before February 2022 it was all peace and quiet in Belgorod region.

But instead of concluding that the "special military operation" had been a mistake, most people I spoke to called for Russia to step up its military action and push deeper into Ukrainian territory.

Former Russian President Dmitry Medvedev is calling for exactly that. In a social media post he wrote: “We can and we should take more land of the Ukraine that still exists. [We should go to] Odesa, to Kharkiv, to Dnipro, Mykolaiv. To Kyiv and onwards.”

But Dmitry Medvedev doesn’t get to call the shots. Vladimir Putin does. We wait to see how he responds to what have been a dramatic few days in southern Russia.

• Read more from Steve here

We can now bring you images sent by Ukrainian officials from the eastern city of Kostyantynivka, where at least 10 people were killed in a Russian attack on a supermarket and post office.

The pictures show the scale of devastation in the city, close to the front-line in the eastern Donetsk region.

Image source, Donetsk region's state emergencies service

Image source, Donetsk region's state emergencies service

Thousands of people appear to have been evacuated from Russia's Kursk region following an incursion by Ukrainian forces.

These images – supplied by Russian officials – appear to show Russian Ministry of Emergency Situations personnel assisting residents during the evacuation.

Russian authorities have declared a state of emergency in the area.

Image source, Reuters

Image source, EPA / Russian Emergencies Ministry

Image source, Reuters

Kyiv’s high-stakes movepublished at 12:27 British Summer Time 9 August

12:27 BST 9 August

James Waterhouse
Ukraine correspondent, reporting from Kyiv

Despite the deployment of reserve troops and orders to evacuate, Russia has been unable to slow the momentum of this Ukrainian advance.

This is clearly more than the probing attacks we’ve seen in the past. Hundreds of soldiers with armoured vehicles are thought to have made it up to 10km (six miles) into Russian territory.

It is a committed assault which has shocked Russia’s military and the Kremlin.

The targeting of the Lipetsk air base is the kind of operation Kyiv has been wanting to do for some time.

Ukraine's armed forces said a warehouse containing hundreds of guided bombs was destroyed.

These are the very tools that Russia has continually terrorised Ukrainian towns, cities, and military positions with for most of its invasion.

Despite long-time western worries of an escalation, the consensus among Ukraine’s allies is that this operation falls within its right to defend itself.

But with Ukrainian forces still outnumbered by the Russians on the battlefield, the line for Kyiv between masterstroke and miscalculation is a fine one.

It's now the fourth day of Ukraine's surprise attack on Russia's Kursk region.

The region borders north-west Ukraine, as you can see from the map below: