UKRAINE is attempting a second surge into Russia with troops eyeing the Belgorod region after smashing into Kursk.
Kyiv's forces are attacking border checkpoints as Putin's soldiers desperately fight back to defend their soil, reports say.
Belgorod governor Vyacheslav Gladkov said the Ukrainians were trying to "break through the border", citing Vlad's defence ministry.
He said: "According to the Russian Defense Ministry, the situation on the border remains difficult but under control.
"Our military is carrying out planned work. Please remain calm and trust only official sources of information."
Rumours of heated Ukrainian attacks are also swirling on Telegram.
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As many as 300 of Volodymyr Zelensky's men have launched towards the Shebekino border crossing, with another 200 to the west at Nekhoteyevka, according to Telegram channel Mash.
The city of Belgorod, which has a population of 340,000, is just 23 miles from the Nekhoteyevka checkpoint.
Reports vary on Telegram with another channel, Shot, claiming there was no fighting at Shebekino and Ukrainians were pushed back in Nekhoteyevka.
Shot said up to 60 soldiers and eight Ukrainian armed vehicles rolled into the border crossing but were met with heavy Russian fire.
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The pro-Kremlin channel claimed Kyiv troops were forced back into a forest, but continue to attack Russian positions.
Ukraine's military chief Oleksandr Syrskyi said his troops had reached the 100-town milestone in their Kursk offensive.
He told Ukrainian TV they also controlled 500 square miles of Russian soil.
In an alarming development, the chief of the United Nations' nuclear agency today flew into Kursk to inspect a power plant, which is located about 25 miles from the heat of battle.
International Atomic Energy Agency boss Rafael Grossi warned there is a "danger or possibility of a nuclear accident" that could cause "serious consequences", Reuters reported.
He told reporters on Tuesday: "We see the plant still operating, but at the same time, the fact that the plant is operating may get even more serious in terms of an eventual action against it.
"When a plant is operating, the temperature is much higher, and if there was the case of an impact or something that could affect it, there would be serious consequences."
Similar fears previously swelled regarding a plant in Ukraine's Zaporizhzhia after Russia invaded in 2022.
Ukrainian and Russian authorities have since accused one another of endangering the site, but disaster has so far been averted.
Ukraine's surge into Kursk had already threatened to spill over into Belgorod.
Belgorod citizens were urged to take shelter just days after the surprise Kursk incursion.
Governor Gladkov wrote in a Telegram message: "The entire territory of the Belgorod region is a MISSILE DANGER.
"Go down to the basement. Stay there until you receive the signal 'all clear missile danger.'"
Moment Ukrainian gunship helicopter blasts Putin’s deadly drone out of the sky
DRAMATIC footage has captured the moment a Ukrainian attack helicopter shoots a Russian drone out of the sky.
The chopper chases down a Shahed-136, known as a kamikaze drone, as the gunman tracks its path.
Gaining a clear line of sight, the Kyiv troop then opens fire with the helicopter's machine gun.
The drone immediately starts emitting a thick trail of smoke as a barrage of bullets blast into it.
Within eight seconds, it starts to plunge from the skies.
Other angles of the attack show the drone plummeting to the ground before it blows up on impact.
A cloud of smoke rises into the air in a Ukrainian triumph.
Shahed drones, designed and built in Iran, are flown in the air to attack ground targets from a distance.
Russia has commonly used them in its invasion, particularly to target important infrastructure.
The US has previously accused Iran of gifting Vlad hundreds of them for his cruel attack on Ukraine.
Around 11,000 people were evacuated from the Krasnoyaruzhsky district in Belgorod, Russian outlet reported.
On Ukraine's side of the border, Vlad launched a major attack overnight - for the second night running - unleashing hundreds of drones and missiles.
Fifteen regions were hit and at least seven were killed.
Authorities said a hotel was blown away in the central city of Kryvyi, killing two, with two more dying in drone attacks in the embattled Zaporizhzhia in the country's southeast.
Ukraine was also forced to intercept strikes bound for capital city Kyiv.
Fierce fighting boils on in Pokrovsk in Ukraine's east as Vlad vies to take the high-priority Donetsk town.
It is being hotly fought over because it sits in vicinity of Ukrainian supply lines.
The Kremlin's deadly strikes are set to keep igniting debate over whether Kyiv should be allowed to use Western weapons to strike deep within Russia, where they say attacks are being launched from.
LEADERS SLAM RUSSIA
US President Joe Biden moved to assure Zelensky that their bond was "unshakeable" in the wake of the attacks.
He added: "Ukrainian officials report that this outrageous attack resulted in the deaths of Ukrainian civilians and targeted more than two dozen critical energy sites.
"Let me be clear: Russia will never succeed in Ukraine, and the spirit of the Ukrainian people will never be broken."
A Ukrainian MP from Kharkiv told Sky News it appeared the bombardments were designed to crush the spirit of the people.
UK Foreign Secretary David Lammy took to X to slam the Kremlin for the attacks.
He said: "The UK utterly condemns Russia’s cowardly missile and drone attacks on civilian infrastructure across Ukraine today.
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"These assaults are in flagrant violation of international law and those responsible must be brought to justice."
Lammy also lamented the death of Brit Ryan Evans, who was working for news agency Reuters when a missile hit his hotel in Kramatorsk on Saturday.