Russian forces maintained a day-long barrage of ⁠drone strikes on Kharkiv, Ukraine’s second largest city, on Thursday, injuring at least two people, local officials said.

Kharkiv Mayor Ihor Terekhov posted reports on Telegram throughout the day and well ⁠into the evening, noting ​strikes ⁠in four city districts. One city official said there had been at least 20 impacts from ⁠drones.

Public broadcaster Suspilne reported new explosions in the city ​after ⁠2am.Mr Terekhov said ‌some of the strikes triggered fires and two people were injured in an evening attack, including an eight-year-old ‌girl.

Reuters Television footage showed firefighters ‌spraying water on a smouldering residence struck by a drone. Parts of the facade were badly damaged and furniture and fixtures ⁠in apartments were smashed.

Further south, in the city of Zaporizhzhia, regional governor Ivan Fedorov said a Russian attack damaged a high-rise apartment building and a local business. No injuries were reported.

Over the border in Russia’s Belgorod Region, regional Governor Vyacheslav Gladkov said 13 people were injured ‌in a series of drone attacks, 11 of ​them in the village of Shebekino, just ‌inside the border.

In Moscow, ⁠Mayor Sergei Sobyanin wrote on Telegram that air defence ⁠units had downed a Ukrainian drone which was heading for the ‌capital well ​after midnight. Two other ‌drones had been intercepted on Thursday.

Russia has issued a stark travel warning to its citizens, advising them to avoid countries with extradition treaties with the United States, citing an increase in “Washington’s punitive justice” since the 2022 invasion of Ukraine.

In a travel advisory, the Foreign Ministry cautioned that Russians risk lengthy prison sentences if handed over to the US.

It highlighted concerns that “with numerous extraterritorial sanctions targeting strategic segments of the domestic economy, many Russians, without even realising it, risk finding themselves in the crosshairs of American law enforcement and intelligence agencies.”

The ministry also alleged, without providing evidence or specific examples, that “US intelligence agencies often engage in fraudulent schemes to lure Russian citizens abroad with lucrative commercial or tourist offers,” leading to immediate detention upon arrival in a third country.

This advisory is specifically aimed at Russians who “have reasonable grounds to believe they may be subject to criminal prosecution by US authorities” or those appearing on US sanctions lists.

Ukraine is already preparing for next winter and working to protect 245 facilities across the country from Russia.

In a post on social media, Volodymyr Zelensky said: “Resilience plans have been approved across the country for every region. Road repairs are also underway after the winter. It is important – at the community level, at the level of regional authorities – not to lose time.

“Every important facility must be protected. There are clear tasks for the regions and major cities regarding alternative generation and the restoration of facilities. Government officials have now ensured the necessary resources and decisions to add cogeneration units to the system.”

Ukraine suffered its coldest winter in more than a decade this year, as Russia launched relentless attacks on its energy system and left Ukrainians without power for much of the winter months.

Ukraine hit five strategic plants and 10 oil refining facilities in March, its ministry of defence has said.

In an update of Thursday, it said Ukraine had carried out a series of large-scale strikes against Russia’s defence industry infrastructure, which spanned from occupied Crimea and the Donetsk and Luhansk Oblasts to deep rear regions of Russia, including Leningrad Oblast.

“Each such strike on russia was part of a systematic effort to dismantle the enemy’s war machine.”

A customers officer in Lviv has been detained on suspicion of murdering an enlistment officer who was fatally stabbed in the neck during a document check on Thursday.

It comes amid growing tension over mobilisation efforts in Ukraine.

The defence ministry said: “Today, Ukraine relies on the military, which in different regions and in different positions, including non-combat, ensure the defence of the state.

“Anyone who kills a soldier – at the front or in the rear – acts against Ukraine. The murderer will face inevitable punishment. This is the only acceptable position.

“The mobilisation system needs changes, and they will be implemented in the near future. But no problem in the system can justify the murder. Condolences to the family. A bright memory to the deceased.”

President Volodymyr Zelensky on Thursday offered to ​provide Ukraine’s expertise in dealing with freedom of navigation in the Black Sea to countries considering how to keep the Strait of Hormuz open amid ⁠conflict in the Middle East.

Zelensky, speaking in his nightly video address, said foreign minister Andrii Sybiha had taken part in a virtual meeting devoted to reopening the Strait of Hormuz, attended ⁠by about 40 countries.

“Ukraine has relevant ​expertise ⁠concerning sea waterways, concerning the defence and reopening of maritime traffic,” he said.

“If (our) partners are ready ⁠to act we will consider how we can strengthen them, ​how ⁠we can apply our ‌expertise, knowledge and technological potential.”

Zelensky offered no further details.

Ukrainian forces have developed technology, including sea drones, that has enabled ‌them during four years of ‌war to score notable successes over Russian ships in the Black Sea and kept Moscow from controlling the waterway.

The president embarked last week ⁠on a tour of Middle Eastern countries as part of a drive to provide them with defence technology it has developed in four years of countering drones, many of them designed in Iran.

He said he was expecting a report on progress in the issue on Friday from ‌Rustem Umerov, Ukraine’s top negotiator in talks on ​reaching a settlement to the war.

On Wednesday, ‌Zelensky said that Ukraine ⁠was already cooperating with Saudi Arabia, the United Arab ⁠Emirates, Qatar, and Jordan, and was also in contact with Bahrain, ‌Kuwait and Iraq. The ​government team was also ‌in talks on potential agreements with ​Turkey and other countries.

The threat of Nato’s break-up alongside the energy crisis is Europe “looks like Putin’s dream plan”, the Polish prime minister has stated.

Donald Tusk, who was previously president of the European Council, wrote on social media: “The threat of NATO’s break-up, easing sanctions on Russia, a massive energy crisis in Europe, halting aid for Ukraine and blocking the loan for Kyiv by Orbán – it all looks like Putin’s dream plan.”

It comes after Donald Trump said he was seriously considering withdrawing the US from Nato.

• Donald Trump’s threat to withdraw the US from Nato over its perceived lack of support for his war in Iran has drawn strong criticism from European leaders.
• Poland’s Prime Minister Donald Tusk described Trump’s stance as ‘Putin’s dream plan’, while French President Emmanuel Macron defended Nato’s integrity.
• Russia launched a record number of drones at Ukraine last month and is intensifying recruitment efforts, including offering financial incentives to students for drone units.
• Russian strategic missile forces conducted drills in Siberia involving Yars intercontinental ballistic missiles, capable of delivering nuclear warheads.
• The US is reportedly seeking to expand its military presence in Greenland, following previous interest from Trump in acquiring the island.

At least five people were killed in an attack that destroyed a postal terminal, Ukrainian officials said on Wednesday.

The incident comes a day after the Kremlin rejected a proposal by Ukraine for a temporary ceasefire over Easter.

Six Ukrainian children will be returned from Russia to their families in Ukraine, the White House said on Thursday, citing efforts made by first lady Melania Trump to expedite their return.

A seventh Ukrainian child will also be returned to their family later this month, the first lady’s office said in a statement.

Ukraine says that nearly 20,000 children have been illegally sent to Russia and Belarus where they are sometimes trained and forced to fight against their own country’s statement.