It's been a year since Alexei Navalny was arrested by authorities at Moscow International Airport and sentenced to two and a half years in a prison camp for allegedly violating parole conditions on fraud charges. 

The fierce critic of Russian President Vladimir Putin had arrived from Germany, where he was recovering at a Berlin hospital from nerve agent poisoning. 

His return and arrest led to protests and a monthslong crackdown on his political network. 

Navalny on Monday took to social media to share his sentiments on the anniversary of his arrest on charges he has maintained are politically motivated. 

"I don't regret it for a second," Navalny said of his decision to return to Russia, only to be arrested. 

Navalny says people must be 'courageous'

Taking stock after a year behind bars, with the possibility of more being added with ongoing cases against him, Navalny said people should not let fear govern them.

"Having served my first year in prison, I want to tell everyone exactly what I shouted to those gathered outside the court when a convoy led me to a police van: Don't be afraid of anything," Navalny added.

"This is our country and we have no other," he wrote.

The Kremlin critic also said that he had read about employees of the Internal Affairs Ministry being "kicked out of office for liking my posts."

"Why live your whole life in fear, and even to be robbed, if you can arrange everything differently — more fairly," Navalny said.

His spokeswoman, Kira Yarmysh, said she regarded January 17 as a "triumphant" moment.

"For me personally, January 17 is the day of victory and the day of absolute triumph. Putin thought that he would kill Navalny. ... Alexey overcame everything and came home — alive, unharmed and even stronger than he was."

Continued imprisonment condemned

Russia has been criticized and condemned by global rights groups not only for Navalny's arrest, but for the ensuing clampdown on political opponents.

Moscow has also been accused being behind the poisoning of Navalny, something the Kremlin denies.

Germany's human rights commissioner, the Green Party's Luise Amtsberg, called for Navalny's immediate release. "His conviction was arbitrary and glaringly disproportionate," Amtsberg said.

International rights group Amnesty International called for Navalny's "immediate release and for the end of brutal reprisals against his supporters," in a post on Twitter.

Russian authorities have stepped up measures against opposition figures and those with links to Navalny.

His political network has been banned and deemed "extremist."

The anti-government critic and his allies were charged in September with setting up an extremist group. This is the fourth criminal case brought against him since his imprisonment.

kb/wmr(dpa, AFP)