Security service claims without evidence that man helped assemble car bomb that exploded near Moscow

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Russia’s FSB security service has accused without evidence a second Ukrainian citizen of preparing the car bomb that killed the daughter of an ultranationalist Russian ideologue this month.

The FSB had previously claimed Ukrainian intelligence plotted the murder of Darya Dugina, a pro-war pundit who was killed when a bomb tore through the Toyota Land Cruiser she was driving near Moscow after a conservative festival.

Fears grow Russia will target country’s gas infrastructure or further cut its supplies to Europe

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Ukrainians are likely to experience the coldest winter in decades, its gas chief has said, as the thermostats on its Soviet-era centralised heating systems are set to be switched on later and turned down.

Yurii Vitrenko, the head of the state gas company Naftogaz, said indoor temperatures would be set at between 17 and 18C, about four degrees lower than normal, and he advised people to stock up on blankets and warm clothes for when outdoor temperatures fall to and beyond the -10C winter average.

Radiation fears over Zaporizhzhia nuclear plant linger amid accusations from Moscow and Kyiv of more shelling near the site

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When Mikhail Sokolov signed up to work for the FSB security services, he never imagined his journey would end here: in a crowded refugee camp on the outskirts of a sleepy town in the rural Netherlands.

“The last six years were a rollercoaster. I am happy I am no longer in the claws of the FSB,” the former FSB informant and staffer for the jailed opposition leader Alexei Navalny’s anti-corruption network said in an interview with the Guardian this week.

[The new names] should perpetuate the memory of significant historical events of Ukraine, as well as famous figures and heroes who glorified Ukraine and fought for the independence of our state.”

Zaporizhzhia nuclear power plant temporarily disconnected from national grid amid fears over disaster; Putin signs decree to increase armed forces

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The Zaporizhzhia nuclear power station was temporarily taken off the Ukrainian power grid. The plant in eastern Ukraine is under Russian occupation and was disconnected from the national power supply for several hours before a last remaining line supplying electricity that cools the reactors was reconnected. Disconnecting the plant raises the risk of catastrophic failure of cooling systems for its reactors and spent fuel rods, which run on electricity.

Vladimir Putin has signed a decree to increase the size of Russia’s armed forces from 1.9 million to 2.04 million, Reuters has cited the Russian state-owned news agency Ria as saying. The figure, which includes a 137,000 increase in the number of military personnel to 1.15 million, will come into effect on 1 January.

The death toll from Russia’s rocket strike on a Ukrainian train station has risen to 25 people. Russian forces attacked a train in the village of Chaplyne, Dnipropetrovsk oblast on Wednesday. Four trains caught fire and the deputy head of the president’s office, Kyrylo Tymoshenko, reported on Telegram that two children were killed in the attack. Russia has since confirmed it was behind the attack.

Russia’s defence ministry confirmed its forces struck the railway station, prompting condemnation from the US and the EU. The US secretary of state, Antony Blinken, said the attack “fits a pattern of atrocities” while the EU’s chief diplomat, Josep Borrell, said those responsible would be held to account.

The UN’s human rights chief, Michelle Bachelet, has called on Vladimir Putin to stop the war in Ukraine and its “unimaginably terrifying” impact on civilians. Bachelet spoke about the six months since the Russian leader ordered his troops into Ukraine during a speech marking the end of her term as the UN’s high commissioner for human rights.

The mayor of the Russian-occupied city of Melitopol, Ivan Fedorov, has said a building allegedly used by Russian-backed officials in the region has been “blown up”. Fedorov, who is not in the city, posted a video on Telegram reportedly showing damage to the building, which he said was being used to plan a “pseudo-referendum” by Russia-backed authorities on whether the region should join Russia.

The head of the Kyiv regional military administration said Russia launched a rocket attack on the region’s Vyshgorod district north of the city centre early on Thursday morning. Oleksiy Kuleba said there were so far no casualties or damage to residential buildings or infrastructure facilities. Ukraine’s armed forces said “several” explosions were heard at about 3am.

The US president, Joe Biden, was set to speak to the Ukrainian president, Volodymyr Zelenskiy, after the announcement of a further $3bn (£2.5bn) in US military aid for Ukraine. John Kirby, the communications coordinator at the national security council, said the phone call would also provide the Ukrainian president with an update on US arms shipments.

Rocket attack in Chaplyne wounds 50 people as country marks six months since Moscow’s invasion

At least 22 people have been killed and 50 wounded in a Russian rocket strike on a Ukrainian railway station, as the country marked six months since Moscow’s invasion on a sombre independence day overshadowed by warnings of further “brutal” attacks.

Addressing the UN late on Wednesday, Ukraine’s president, Volodymyr Zelenskiy, said the rockets struck a train in a station in the town of Chaplyne, about 145km (90 miles) west of Donetsk in eastern Ukraine.

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The UN has said it is “very concerned” about plans by Russian-backed authorities to hold trials for captured Ukrainian soldiers in Mariupol.

Pro-Russian officials appear to be installing metal cages in a hall in Mariupol as part of plans to establish what they were calling an “international tribunal”, a UN rights office spokesperson said, adding that such a process could itself amount to a war crime.