Alexei Navalny was arrested by police officers at the border shortly after arriving at Moscow's Sheremetyevo airport. /AP
Russian opposition leader Alexei Navalny has been arrested by police on his arrival back in Russia after spending months in Germany while recovering from nerve agent poisoning.
Before the flight carrying Navalny and his wife, Yulia departed from Berlin's Brandenburg airport heading for Moscow's Vnukovo airport, the politician told reporters he was "very happy" to be returning home.
The plane was diverted to the nearby Sheremetyevo airport, with hundreds of supporters and riot police waiting for the 44-year-old Kremlin critic at Vnukovo airport. Sheremetyevo is one of four international airports within Moscow.
According to news agency AFP, which had journalists on board the flight carrying Navalny, the pilot first announced a 30-minute delay due to a "technical problem" before saying it would be diverted.
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Russia's prison service said on Thursday that Navalny, who blamed his poisoning on the Kremlin, faces immediate arrest once he returns. The Kremlin has repeatedly denied a role in the poisoning.
"They will arrest me? They will arrest me? That's impossible, I'm an innocent person. I feel I am a citizen of Russia who has the full right to return to his home," Navalny said at Berlin airport. But shortly after his arrival back in Russia, he was detained by police.
"Alexei was taken away by police officers at the border. With no explanation given," Navalny's spokesperson Kira Yarmysh confirmed.
Back in December, the country's Federal Penitentiary Service (FSIN) warned that Navalny would face time in prison if he failed to report to its office line with the terms of a suspended sentence and probation he received for a 2014 conviction on charges of embezzlement and money laundering.
"I feel I am a citizen of Russia who has the full right to return to his home," Navalny told reporters at Berlin's Brandenburg airport before flying back to Russia. /AP
The conviction was rejected by both Navalny, who called it politically motivated, and the European Court for Human Rights, which ruled that the charge was unlawful.
The FSIN issued a warrant on Thursday after Navalny failed to report to its office.
The prison service, which has called for a Moscow court to turn the three-and-a-half year suspended sentence into real jail time, said it is "obliged to take all the necessary action to detain Navalny pending the court's ruling."
Vnukovo airport banned journalists from its terminal for the arrival of Navalny, citing epidemiological reasons, while security measures were heightened, including several prisoner-transport vehicles parked outside.
Police detained several of Navalny's top allies at the airport shortly before his arrival, including prominent Moscow activist Lyubov Sobol.
Supporters gathered at the terminal despite the airport banning mass gatherings amid the COVID-19 pandemic, but despite the clashes, Navalny never arrived at Vnukovo airport as planned.
Security measures were heightened at Vnukovo airport, with several of Navalny's top allies and supporters detained shortly before his arrival. /AP
What happened to Navalny?
Russia's opposition leader fell ill while onboard a flight from Siberia to Moscow on August 20, 2020 and was transferred to a hospital in Berlin for further treatment.
Tests in Germany, France and Sweden and the Organization for the Prohibition of Chemical Weapons all found that Navalny was exposed to the dangerous Novichok nerve agent, despite Russian authorities insisting that the doctors who treated him in Siberia before he was transferred to Germany found no traces of poison.
Read more: Navalny poisoned with Novichok, German tests reveal
Navalny has blamed his poisoning on the Kremlin, but it as repeatedly denied playing a role.
In October, European Union foreign ministers backed a plan to impose sanctions on six Russian government staff over the poisoning. Russia has since responded by banning unnamed European Union officials.
"We will continue to respond appropriately to unfriendly actions by western countries," Russia's foreign ministry said.
Last month, Navalny released a recording of a phone call he said he made to a man he described as an alleged member of the Federal Security Service (FSB), which he alleged poisoned him and then tried to cover it up. The FSB has since claimed the recording was fake.
Navalny, alongside Bellingcat investigative journalist Christo Grozev had put together accusations that the FSB had tracked the Kremlin critic for several years.
The report identified 40 flights where agents had accompanied Navalny using different aliases, adding that "there was statistically zero chance this could be a coincidence."
In response to the claims Dmitry Polyanskiy, the deputy head of Russia's UN mission, said on Twitter: "How can a sane person believe in such nonsense?"