1. Russian exodus as thousands cross borders to escape possible conscription
Russia's first "partial mobilisation" since World War II has prompted an exodus of military-age men fleeing the country, as well as widespread protests and some attacks on military recruitment centres.
The number of Russians entering the European Union has risen by almost a third in a week, according to the EU's border agency Frontex.
It says 66,000 Russian citizens entered the EU in the week from September 19-25 — a 30% rise on the preceding week — and links the move to the partial mobilisation.
Most came in through Finnish and Estonian border crossing points, Frontex said in a statement, adding that the number of crossings had significantly increased in Finland since Russia's announced mobilisation — with 30,000 arriving in the last four days.
The agency says most have EU or Schengen permits, visas or dual citizenships. It estimates that illegal border crossings are likely to rise if Russia closes its borders for potential conscripts. Several European countries bordering Russia have begun restricting Russians travelling solely for tourism or leisure.
The number of Russians arriving in neighbouring Georgia has almost doubled to nearly 10,000 a day after Putin's announcement last week. Meanwhile, around 98,000 Russians have crossed into Kazakhstan in the last seven days, officials say.
Russian independent media are now speculating that Putin may follow up by declaring martial law and shutting the nation’s borders to certain travellers.
Kremlin officials have declared plans to set up a military recruitment office on one of the main border routes to Georgia.
Russia has also pledged to correct "mistakes" in the mobilisation process which has seen citizens being enlisted without military experience.
2. Fears that occupied Ukrainians could be enlisted in 'mobilisation'
Ukrainian President Volodymyr Zelenskyy has slammed Russia's reservist call-up as “an attempt to provide commanders on the ground with a constant stream of cannon fodder.”
On Monday, Zelenskyy vowed that the Ukrainian military will push efforts to take back “the entire territory of Ukraine".
Meanwhile, some Ukrainian citizens in Russian-occupied cities have expressed fears that they may be called up to fight for Russia.
NGOs have reported that young Ukrainian men attempting to leave occupied areas are being turned back by Russian soldiers.
The claims were also repeated by Ivan Fedorov, the exiled Ukrainian mayor of Melitopol in the region of Zaporizhzhia.
"Our residents are frightened, they are panicking, they don't know what will happen tomorrow, and when people will start being called up (to Russia's army)," he told a news briefing via video link.
Fedorov said that the Vasylivka crossing -- the only open route to Ukraine -- had been closed to men aged 18 to 35 for four days and was completely shut on Sunday.
3. Final day of 'voting' in 'sham referendums' in Ukraine
Russian-led "sham referendums" in four regions of eastern and southern Ukraine have entered a final day on Tuesday.
According to state media, the first partial voting results showed an overwhelming majority in favour of becoming part of Russia.
The Kremlin is expected the use the results as a pretext to annex Donetsk, Kherson, Luhansk, and Zaporizhzhia, which make up about 15 per cent of Ukraine.
But Ukraine and its Western allies have slammed the five-day votes as a "sham" while images on social media showed armed Russian troops going door-to-door to pressure residents into voting.
Ukraine's presidential adviser said on Tuesday any Ukrainian "collaborators" who help Russian-backed referendums will face treason charges and at least five years in jail.
President Vladimir Putin is likely to announce the accession of the four occupied regions of Ukraine during his address to parliament on 30 September.
"Russia's leaders almost certainly hope that any accession announcement will be seen as a vindication of the special military operation and will consolidate patriotic support for the conflict", the UK Defence Ministry said on Tuesday.
Meanwhile, the Ukrainian foreign minister Dmytro Kuleba has reiterated that the planned annexation "will not change anything".
On Tuesday, Kuleba urged the European Union to impose further economic sanctions on Russia as punishment for staging the votes.
The final day of "voting" came as a senior Kremlin official issued the bluntest warning yet that Russia is prepared to use nuclear weapons in Ukraine.
Dmitry Medvedev, a former Russian president, said on Tuesday that Russia had the right to defend itself with nuclear weapons if it is pushed beyond its limits and that this is "certainly not a bluff".
"I believe that NATO would not directly interfere in the conflict even in this scenario," Medvedev added.
"The demagogues across the ocean and in Europe are not going to die in a nuclear apocalypse."
Medvedev, a close ally of Putin who now serves as deputy chairman of Russia's Security Council, has regularly issued volatile statements amid the war.
Putin has himself warned that once the Russia-held regions are absorbed, Moscow will defend its territory with “all available means”, including nuclear weapons.
The US has warned Moscow that it would respond "decisively" with "catastrophic consequences" to any use of nuclear weapons.
4. Heavy fighting continues on the ground
Ukrainian and Russian forces were locked in heavy fighting across Ukraine on Tuesday, Kyiv officials said.
President Zelenskyy said the eastern Donetsk region remained his country’s top strategic priority but described the military situation as “particularly severe”.
Fighting also engulfed several towns in the north, south, and west as Russian troops try to advance to counter Ukraine's recent progress. Residential buildings in Zaporizhzhia and Mykolaiv were reportedly damaged overnight.
The Ukrainian armed forces' southern command claimed that its counter-offensive in Kherson had resulted in enemy losses of 77 soldiers, six tanks, five howitzers, three anti-aircraft installations and 14 armoured vehicles.
Kyiv has pressed on with a campaign to put out of action four bridges and other river crossings to disrupt supply lines to Russian forces in the south.
The regional administration in Odesa meanwhile says that Russia carried out at least five drone attacks on targets in the last few days.
Turkish Foreign Minister Mevlut Cavusoglu has reported that Moscow was ready to resume negotiations with Ukraine but had “new conditions” for a ceasefire.
5. Nord Stream pipelines suffer damage and loss of pressure
The operator of the Nord Stream gas pipeline system has reported that three offshore lines sustained "unprecedented" damage in one day.
Sweden's Maritime Authority said on Monday that at least two leaks had been found in the Nord Stream 1 pipeline.
Denmark is also restricting shipping and has raised power preparedness levels after another leak on the nearby Nord Stream 2 pipeline was discovered.
It was not immediately clear what had caused the leaks, which could take weeks to drain.
Neither incident occurred as gas was being pumped to Europe. Both Russia and EU countries have refused to rule out sabotage for the leaks.
The Nord Stream pipelines have been at the centre of the energy dispute between Europe and Russia since the start of the war in Ukraine.
A drop in Russian gas supplies has caused energy prices to soar across the continent, putting pressure on governments to help ease the pain of sky-high bills for their citizens.
Officials said the leaks did not pose any threat to energy supplies given that Russia is not supplying gas through them, and experts said the environmental impact would be limited.
Danish authorities have nevertheless asked ships to steer clear of the Baltic Sea island of Bornholm as countries scrambled to investigate.
The leaks and pressure damage come as the new Baltic Pipe -- delivering Norwegian gas to Poland -- is due to be inaugurated later on Tuesday.
6. Ukrainian POWs face systematic mistreatment -- UN investigators
UN human rights investigators say that a "vast majority" of Ukrainian prisoners of war appear to be facing “systematic” mistreatment.
Prisoners have reportedly been tortured, both when they are captured and when they are transferred into areas controlled by Russian forces.
Investigators say they have documented examples of arbitrary detention, summary executions, torture, and sexual violence.
The head of the UN office called on Moscow to address these "grave violations" of international law.
The team also found that some Russian POWs had been subjected to torture and ill-treatment, mostly during capture or during transit to places of internment.
The statement is the first comprehensive look at rights violations and abuses committed by both sides in Ukraine after Russian forces invaded on February 24.
The mission has been working in the country since fighting first broke out in 2014 but stated that it had not been given "unimpeded access" to areas controlled by Moscow or its affiliates.
7. Japan protests against diplomat spying charge
Japan has protested after a consulate official in Russia was detained on Monday on allegations of spying.
A Japanese diplomat was given 48 hours to leave Russia on Monday after being declared “persona non grata" on Monday.
Tokyo has denied the espionage accusations and has accused Russian authorities of abusing the official during interrogations.
The official was questioned with his eyes covered, his hands and head pressed and immobilised, Japan’s Foreign Ministry said on Tuesday.
Japan says it has now lodged a formal protest to demand an apology.
“The alleged illegal activity insisted by the Russian side is completely groundless,” Chief Cabinet Secretary Hirokazu Matsuno told reporters, adding that Japan's Foreign Ministry had summoned Russia’s ambassador.
Russia's treatment of the consulate official during the interrogation was “intimidating” and violated international agreements, Matsuno said.
“It is extremely regrettable and absolutely unacceptable,” he added.
The diplomat has since been released with no health problems and is set to return to Japan on Wednesday.
Relations between Tokyo and Moscow worsened over Japan’s sanctions against Russia’s invasion of Ukraine.