Drones shot down over Russia as Zelenskyy addresses Ukraine's invasion of Kursk for first time

We've just been hearing from our defence and security analyst Professor Michael Clarke who says Ukraine has "launched an attack of complete astonishment" against Russia this week. 

As we've been reporting, Ukraine has invaded the Kursk region of Russia - prompting the evacuation of more than 70,000 people and emergency security measures to be activated across three Russian regions. 

Professor Clarke says the evidence points to Ukraine "winning this battle insofar as it goes".

"They haven't just launched a surprise attack - they've launched an attack of complete astonishment. They've astonished the Russians, astonished Western backers," he says. 

As things stand, the shock value of this surprise assault is "working in Kyiv's favour". 

The pocket that has driven into Russian territory is at least 35 miles long and about 15 miles deep, he says. 

"That's pretty powerful... the Ukrainians must be very pleased with where they are now."

Can Ukraine maintain its offensive?

Asked whether Ukraine's forces will be able to hold their position, Professor Clarke says they will need to be reinforced. 

He says the equivalent of about three or four brigades are in Russia, and these are "top level, elite troops". 

The analyst says this shows Ukraine is serious about this offensive. 

No information has been given about Ukraine's aims, and they have tightly controlled information security around the invasion, but Professor Clarke says Kyiv is undoubtedly hoping it will draw in good units of the Russian army and relieve Ukrainian frontlines elsewhere. 

Anecdotal evidence so far suggests Moscow is pulling its better units out of the south of Ukraine, including in the areas of Chasiv Yar and Pokrovsk. 

Russia "will do whatever it takes to eliminate this pocket", he says.

'Putin can't let this stand'

Professor Clarke says there is highly likely to be a response from Russia. 

"The idea of having a piece of their territory seized for the first time since 1941... Putin can't let that stand," he says. 

Moscow will "counter attack as strongly as they need to and this battle will get a great deal more ferocious yet". 

For Ukraine's part, Professor Clarke says Kyiv is "gambling on this offensive working" and "so far it's paying off". 

The longer the Ukrainians hold on in Kursk, the tougher it will be for Russia to push them out, he says. 

Four injured in shelling on Russian town

A town in Russia's Belgorod region is facing shelling from Ukrainian forces today, local governor Vyacheslav Gladkov has said. 

Four people were injured, including three men with shrapnel wounds who were taken to hospital in Shebekino. 

They are said to be in a moderate condition. 

Shelling also damaged an apartment building, a bus stop and a bus, Mr Gladkov said. 

The region is currently under emergency measures after Ukrainian forces crossed the border into neighbouring Kursk region. 

Ukrainian media outlets earlier reported on a video appearing to show Ukrainian troops in the village of Poroz in the Belgorod region.

Poroz is about 130 kilometres west of Shebekino. 

Zelenskyy says North Korean missile was used to attack Kyiv

We've just heard from the Ukrainian president, who has commented on last night's Russian attack on Kyiv. 

Volodymyr Zelenskyy offered his "deepest condolences" to the family of the father and son killed in the attack. 

He said preliminary information suggests Russia used a North Korean missile in the attack.

"Pyrotechnic experts are still working to determine the exact data regarding this missile," he wrote on X.

The president said Russia has launched more than 30 missiles and 800 guided aerial bombs at Ukraine in the last week. 

"Ukrainians are deeply grateful to all our partners who provide us with air defense systems and combat aircraft," he said. 

"However, to truly stop Russian terror, we need not only a full-fledged air shield that can protect all our cities and communities, but also strong decisions from our partners - decisions that will lift restrictions on our defensive actions." 

A block of flats has sustained damage and a car was set alight following an aerial attack on Russia's Kursk region overnight. 

Local authorities said the damage was caused by a downed Ukrainian missile. 

Kursk officials earlier said 13 people were injured in the attack. 

While the full extent of Ukraine's invasion of the Kursk region of Russia remains unclear, the town of Sudzha has been a focus over the last few days.

Located around 10.5km (6.5 miles) from the border with Ukraine, it is around 100km from the regional capital, the city of Kursk.

Sudzha had been home to around 5,000 people and is the site of an important gas transportation hub.

But after Ukrainian forces broke across the border on Tuesday in a shock counter-offensive, it is no longer certain that Sudzha is under Russian control.

Ukrainian troops that have crossed the border - and it's thought there could be several thousand - have been reportedly expanding the areas under their control. 

Ukrainian troops enter Belgorod region

Ukrainian media outlets are reporting that Kyiv's forces appear to have entered Russia's Belgorod region. 

Troops previously entered the border into the Kursk region and fighting has been taking place there. 

Media outlets, including Ukraine's Suspilne, are now reporting on a video of five uniformed Ukrainian troops standing outside a building as one says: "I wish you health, the 252nd battalion is in the village of Poroz, Belgorod Oblast. Glory to Ukraine!" 

The soldiers were holding the battalion's flag and a Georgian flag. 

A sign on the building behind them reads "Porozovsky Village Club". 

The video has not been independently verified by Sky News, but Ukrainian-based fact-checking project VoxCheck confirmed the video was filmed in Poroz, three kilometres away from the Ukrainian border.

It's not clear when the video was filmed, or whether it might have been part of a raid. 

Zelenskyy says Ukraine is 'restoring justice'

As we've been reporting, Volodymyr Zelenskyy has acknowledged the invasion of Russia's Kursk region for the first time. 

The Ukrainian president said his country is "restoring justice" and putting "pressure on the aggressor".

Russia 'seeking to downplay situation in Kursk' as Kremlin refuses to declare martial law

The Kremlin is seeking to "downplay" the scale of fighting in its Kursk region and prevent domestic panic or backlash, analysts have said. 

Russia announced a counter-terrorism operation yesterday after Ukrainian forces invaded Kursk, but the US-based Institute for the Study of War has said there was a conscious decision not to declare a state of war or martial law. 

It said there was a "reluctance to take more drastic measures to respond to the situation".

Declaring martial law would have allowed Russian authorities to prohibit rallies and demonstrations, enact curfews, and organise the production of defence articles for the military.

Russian opposition outlet Verstka reported earlier this week that a source close to the Russian Federation Council's defense committee said the presidential administration had recommended Russian deputies and senators not comment on the events in Kursk "until further notice". 

The ISW said: "Russian President Vladimir Putin has refrained from officially declaring a state of war, has repeatedly demonstrated his unwillingness to transfer Russian society fully to a war-time footing, and has forgone declaring general mobilization as part of wider efforts to prevent domestic discontent that could threaten the stability of Putin's regime."

Belarus sends troops to reinforce border with Ukraine

We've been reporting that Belarus has claimed it shot down unspecified objects launched from Ukraine, and we can bring you more detail on that story now. 

Belarusian President Alexander Lukashenko has said his country's air forces destroyed several of "about a dozen" Ukrainian drones after they violated his country's airspace in the Mogilev region bordering Russia. 

Mr Lukashenko - a close ally of Vladimir Putin - said other drones were later destroyed near the Russian city of Yaroslavl. 

I don't understand why Ukraine had to do this. We have to look into it," the BelTA news agency quoted him as saying. 

"But we have...made ourselves clear and conveyed to them that any provocation will not go unanswered."

In response, Belarus has sent more troops to reinforce its border with Ukraine. 

The foreign ministry also summoned Ukraine's charge d'affaires, demanded measures to ensure such incidents would not recur and suggested a repeat would prompt Belarus to consider whether Kyiv's diplomatic presence in Minsk was "appropriate".

-SKY NEWS