A burned car is seen in front of an apartment building damaged after shelling by the Ukrainian side in Kursk, Russia, on Sunday, August 11, 2024.
CNN  — 

Ukrainian President Volodymyr Zelensky has confirmed Kyiv’s troops are fighting inside Russia, days into the surprise Ukrainian cross-border incursion into Russia’s Kursk region that has become a major embarrassment for the Kremlin.

“Ukraine?is proving that it really knows how to restore justice and guarantees exactly the kind of pressure that is needed – pressure on the aggressor,” Zelensky said in his nightly address to the nation on Saturday, thanking “every unit” of Ukraine’s armed forces for making it possible “to push the war out into the aggressor’s territory.”

The statement marked the first time Zelensky officially acknowledged the incursion, which took by surprise both Russia and Ukraine’s allies. Ukrainian officials have for days remained tight-lipped about the operation, even as photographs, videos and firsthand reports of Ukrainian soldiers inside Russia started to emerge.

Ukraine has repeatedly targeted the border region of Belgorod with airstrikes and pro-Ukrainian sabotage groups have conducted limited cross-border attacks, but the Kursk operation marked the first time that regular Ukrainian and special operations units have entered Russian territory.

Moscow has been scrambling to contain the attack. Russian authorities imposed a sweeping counter-terror operation in Kursk and two other border regions and tens of thousands of people have been evacuated from Kursk.

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Updated 10:02 PM EDT, Sun August 11, 2024
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Video shows burnt-out Russian trucks with bodies in Kursk region
00:49 - Source: CNN

On Sunday, Zelensky said Russian forces started a fire at the Russian-controlled Zaporizhzhia Nuclear Power Plant in southern Ukraine. Posting a video showing a large plume of smoke coming out of one of the towers on the plant’s territory, Zelensky said radiation indicators were normal but blamed Russia for using the nuclear plant “to blackmail Ukraine, and all of Europe and the world.”

Russia has accused Ukraine of starting the fire on the plant’s territory.

Now into its sixth day, the attack on Kursk is a significant development in the more than two-year old conflict. The surprise factor appear to have worked: as of Sunday, Russian troops seemed to struggle to stop the Ukrainian advances and push Kyiv troops back.

Zelensky said thousands of strikes on Ukraine’s territory launched from Russia’s Kursk region deserve a fair response.

“Since the beginning of this summer alone, almost 2,000 strikes have been made on our Sumy region from districts of the Kursk region only: artillery, mortars, drones. We also document every missile strike,” he said adding that “every one of these strikes deserves a fair response.”

Recent Ukrainian missile and drone strikes on Russia show that Kyiv has been living up to Zelensky’s words.

Russia on Sunday it foiled a Ukrainian attack that launched drones and Tochka-U tactical missiles. Its Ministry of Defense said it destroyed 14 drones and 4 Tochka-U tactical missiles over the Kursk region, 16 drones over the Voronezh region, three drones over the Belgorod region,?and one drone each over the Bryansk and Oryol regions.

The latest report by the?Russian Defense Ministry (MOD) indicated that Ukrainian troops have advanced up to 30 kilometers (18.6 miles) inside?Russia.

The ministry said on Sunday that its forces had engaged in combat with Ukrainian troops “in the areas of the settlements of Tolpino, Zhuravli and Obshchy Kolodez.”

Ukrainian soldiers raise flags in Kursk region

The?Institute for the Study of War (ISW), a US-based conflict monitoring group, said in its latest assesment on Sunday that geolocated footage and Russian reporting from Saturday indicated that Ukrainian forces maintained their positions in the region and have advanced slightly further.

By Friday Russian authorities had lost control over at least 250 square kilometers of territory, according to several independent analyses and CNN’s mapping.

Videos posted on social media appear to show Ukrainian troops taking down Russian flags in Russia’s Kursk region and replacing them with Ukrainian flags.

One video geolocated by CNN, which was posted across social media on Saturday, shows Ukrainian soldiers taking down a Russian flag at the Sverdlikovo village council building in the Sudzhansky district and throwing it to the ground.

Another video geolocated by CNN on Sunday, shows Ukrainian soldiers standing on a Russian flag outside the Guyevo village club building also in the Sudzhansky district. A Ukrainian soldier – holstered up by another soldier – is seen climbing towards the top of the building, raising a Ukrainian flag.

The governor of?Kursk?region has urged authorities there to speed up evacuations on Sunday. More than 76,000 people from the border areas had left their homes as as of Saturday, according to the Russian state news agency?TASS .

Russian authorities imposed a “counterterrorist operation regime” in Kursk, Bryansk and Belgorod regions on Friday, stopping short of declaring state of war or martial law.

ISW said this was was likely an attempt by the Kremlin to deliberately downplay the assault to prevent domestic panic or backlash over the fact that Russia was unable to defend its own borders.

“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 (his) regime,” the ISW said in its update.

The counterterrorist regime officially gives Russian authorities wider powers, including the ability to monitor telephone conversations and restrict communications and limiting the movement of people.

Russia strikes Kyiv

The surprise attack in Kursk, which Putin called a “major provocation,” has been a significant win for Kyiv as it continues to struggle to hang onto its territory along parts of the 1,000 kilometer frontline.

Moscow has pushed on with its?slow, grinding offensive, edging closer in recent weeks to several strategically important towns and roads in eastern Ukraine.

Early on Sunday, Moscow launched drone and missile attacks against Kyiv region, according to local officials. A four-year-old boy and his father were killed in?a Russian strike in Brovary, just east of the capital city, the officials said, adding that another child was seriously injured.

Ukrainian servicemen ride a military vehicle near the Russian border in Sumy region, Ukraine, on August 11, 2024.

Mykola Oleshchuk, Ukrainian Air Force commander, said Russia attacked Ukraine using, among other weapons, North Korean KN-23 ballistic missiles and Iran-made Shahed drones. CNN cannot independently verify that claim.

And Zelensky claimed on Sunday that a missile made in North Korea killed the father and his son, saying “our experts have precisely identified the type of missile, and we know the exact area of?Russian territory from which it was launched.”

CNN has not been able to independently verify the claim but the White House has previously reported that?Russia?has fired North Korean-supplied short-range ballistic missiles into Ukraine.

The attack came after a strike on a supermarket in the Ukrainian town of Kostiantynivka in Donetsk region left at least 11 people dead and 37 injured, according to authorities.

In a video statement released on Sunday, Zelensky said that “this week alone, the Russian army launched more than 30 missiles and over 800 guided aerial bombs,”

It has been a deadly summer for Ukrainian people, with July marking the deadliest month for civilian casualties since October 2022, according to UN human rights monitors.

The UN Human Rights Monitoring Mission in?Ukraine?(HRMMU)?said at least 219 civilians were were killed and 1,018 injured in what the agency previously called a “deadly wave of missile strikes on densely populated areas of Ukraine.”

This story has been updated with additional developments.

CNN’s Eve Brennan, Isaac Yee, Radina Gigova and Olga?Voytovich?contributed reporting.