Russian troops have seized Europe’s largest nuclear power plant after it was shelled overnight, sparking a fire but no release of radioactive material, the UN’s atomic watchdog has said.

The attack on the southeastern city of Enerhodar and its Zaporizhzhia nuclear plant had led to fears of a nuclear disaster, with immediate condemnation from world leaders, and EU and NATO foreign ministers considering fresh sanctions.

Three Ukrainian troops were killed and two wounded in the assault, according to the Ukrainian state nuclear company.

Rafael Mariano Grossi, director general of the International Atomic Energy Agency (IAEA), said a training centre that was not part of the reactor was hit by a Russian “projectile” and two security personnel were injured in the subsequent blaze which was put out by firefighters.

“All the safety systems of the six reactors at the plant were not affected at all and there has been no release of radioactive material,” he said, adding that the Ukrainians were still running operations but the situation remains “very unstable”, with Russian forces in control of the overall site.

Ukraine invasion – Live updates

Key developments:

• Mariupol, the main port on the Sea of Azov, remains surrounded by Russian forces and under heavy bombardment
• 47 people have reportedly been killed in Russian airstrikes in Chernihiv
• Russian troops have entered Mykolaiv – an hour up the road from key city of Kherson
• Fierce fighting between local forces and Russian troops on outskirts of Enerhodar – with casualties reported
• Russian parliament passes a bill introducing sentences of up to 15 years in prison for “fake” information about military action
• President Volodymyr Zelenskyy says only ‘urgent action by Europe’ can stop the Russians

With the war into its second week, Russian forces have continued their assaults on Ukraine’s major cities with Reuters news agency reporting 47 people have been killed in Russian airstrikes on a residential area of the northern Ukrainian city of Chernihiv – citing local officials.

Mariupol is still being bombarded with unrelenting artillery fire, and Kherson – strategically located in the south at the mouth of the Dnieper River’s exit into the Black Sea – remains under siege as the first major city the Russians say they control.

And while the huge Russian military convoy north of Kyiv has stalled, analysts believe a major assault on the port city of Odessa might soon begin.

‘Threat of nuclear disaster’

The IAEA said the fire has not affected essential equipment or caused radiation levels to change, while US officials have also stressed reactors at Zaporizhzhia power station are protected by robust containment measures, and were safely shut down.

There is only one reactor operating, at 60% of its capacity, Mr Grossi confirmed.

Pentagon spokesperson John Kirby said the attack showed how reckless the Russian invasion has been. “It just raises the level of potential catastrophe to a level that nobody wants to see,” he told CNN.

Ukrainian officials had earlier said there was a “real threat of nuclear danger”, with foreign minister Dmytro Kuleba warning: “If it blows up, it will be 10 times larger than Chernobyl.“

Did the Russians mean to strike the nuclear power plant?

It is unclear whether the decision to attack the plant was deliberate.

Professor Michael Clarke, a security analyst, told Sky News it was likely the Ukrainians surrendered the site “to avoid another Chernobyl”.

Zelenskyy calls for Europe to take action in overnight video

Ukraine’s president gave an emotional speech overnight in which he warned an explosion at the nuclear power plant could spark “the evacuation of Europe”.

Volodymyr Zelenskyy added: “Only urgent action by Europe can stop the Russian troops. Do not allow the death of Europe from a catastrophe at a nuclear power station.”

Energy experts have said there is nothing to indicate an impending disaster, nonetheless, the assault triggered late-night phone calls between Mr Zelenskyy and Western leaders – with the US Energy Department activating its nuclear response team as a precaution.

Russia has already captured the defunct Chernobyl plant that lies about 62 miles (100km) north of Kyiv – the site of the 1986 accident that is considered to be the worst nuclear disaster in history.

NATO chief warns days ahead ‘likely to be worse’

The war in Ukraine will cause more deaths and destruction over the coming days, NATO Secretary General Jens Stoltenberg said, describing the Russian attack on the nuclear plant as “reckless” and a “dangerous moment”.

The Kremlin is demanding Ukraine never joins NATO, and the alliance’s chief accused Russian President Vladimir Putin of wanting to “create a sphere of influence”, urging him to stop the war immediately and without conditions.

US Secretary of State Antony Blinken said the pact would defend “every inch” of NATO territory from attack. “Ours is a defensive alliance. We seek no conflict. But if conflict comes to us, we are ready,” Mr Blinken said.

An emergency meeting of the UN Security Council is taking place following Russia’s attack on the plant.

A third round of ceasefire talks could happen next week, as a presidential aide said on Friday that Mr Zelenskyy would not make any concessions that could humiliate his people.

Biggest attack on European state since World War Two enters ninth day

On Thursday, footage from Enerhodar showed flames and black smoke rising above the city, which had a population of 50,000 before the war began.

Energoatom, the company that operates Ukraine’s nuclear power plants, had warned: “Many young men in athletic clothes and armed with Kalashnikovs have come into the city. They are breaking down doors and trying to get into the apartments of local residents.”

Ukraine’s Prime Minister Denys Shmyhal has called on the West to close the skies over the country’s nuclear plants as fighting intensifies – warning in a statement that “the security of the whole world is at stake”.

But the US and NATO allies have ruled out establishing a no-fly zone because such a move would pit Russian and Western military forces against each other.

Russia may attempt a provocation to give Belarus a reason to join the attack

Sky’s security and defence editor Deborah Haynes says Ukraine’s armed forces have said it is possible that Russia may attempt to create a provocation at the Ukrainian border with Belarus to give the Belarusian regime a pretext to send its troops to join Russia’s invasion, according to a military update.

Russian forces continue to target cities

Mariupol, the main port on the Sea of Azov, remains surrounded by Russian forces and under heavy bombardment, the UK Ministry of Defence said in its latest update on Friday.

Officials say water and power has been cut off and they are unable to evacuate the wounded.

The northeastern city of Kharkiv, like Chernihiv, has been under attack since the start of the invasion, but the Ukrainians are holding out in the heavily shelled city.

Movement at stalled miles-long Russian military convoy near Kyiv?

It has been stationary for three days, but there are now indications that some of the BTGs – the battalion tactical groups – are fanning out westwards as if they are going to go to the south of Kyiv with the encirclement of the capital almost evitable, according to Prof Clarke.

Two separate but synchronised operations in north and south

Moscow’s strategy has always been to take the southern coast and connect Crimea to Russia and to remove the regime in Kyiv.

Russian forces have come out of Crimea and have turned both east and west, with those advancing towards the Donbas region in eastern Ukraine aiming to link up in Mariupol with Russian forces coming from Russia.

The stalled Russian military convoy north of Kyiv is still 16 miles (25km) from the capital’s centre, the US has said, while analysts believe Odessa on the northwestern shore of the Black Sea is the next likely target.

The Ukrainian Defence Ministry said the “Russian Black Sea Fleet consisting of four large landing ships accompanied by three rocket boats” is approaching the country’s third largest city.

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