A Russian court has sentenced opposition politician Aleksei Navalny to 20 days in jail on charges of repeatedly violating legislation governing protests and demonstrations.
The Simonovsky district court in Moscow issued the sentence on October 2 after finding the prominent foe of President Vladimir Putin guilty of calling for unsanctioned rallies.
The sentence means Navalny will miss a demonstration planned in Putin's hometown of St. Petersburg on October 7, the president's 65th birthday.
"Old man Putin is so scared of our meetings in the regions that he decided to make himself happy with a small gift for his birthday," Navalny said on Twitter after the ruling.
"This is an outrageous decision. We will appeal," one of his lawyers, Olga Mikhailova, said of the court decision.
Navalny was facing a sentence of up to 30 days.
He was detained by police on September 29 in Moscow and prevented from boarding a train to Nizhny Novgorod to attend a presidential campaign rally in the center of the Volga River city.
He was released after being held for about 10 hours, in a move that prevented him from speaking at the rally.
Police said that Navalny was detained for repeatedly calling for people to attend unsanctioned public gatherings.
Navalny has vowed to keep holding rallies, including the demonstration in St. Petersburg later this month.
"We are not going to stop what we do, whatever the obstacles," Navalny told journalists waiting for him outside the Moscow police station after his release.
Navalny spoke on October 1 at a rally in the northern city of Arkhangelsk.
Since announcing last year that he would run in the March 2018 presidential election, Navalny, 41, a vocal critic of Putin, has opened more than 60 campaign offices in regions across of Russia. He and supporters have held dozens of rallies, including several in recent weeks that have drawn crowds of hundreds or thousands.
Russian election officials have said Navalny, an anticorruption activist who received 27 percent of the vote in the 2013 Moscow mayoral election, is not eligible to run in the election because of a felony embezzlement conviction in a case dating back to 2009. Navalny contends that he is innocent and says that case and others launched against him were engineered by the Kremlin to punish him for his opposition activities.
Earlier this month, Human Rights Watch said that Navalny's campaign supporters were being "systematically" harassed and attacked by nationalists, Putin supporters, and law enforcement officials.
Navalny's national campaign coordinator, Leonid Volkov, and about a dozen activists were detained by the authorities in Nizhny Novgorod on the day of the rally there.
A separate Moscow court ruled on October 2 that Volkov committed the same legal violation and ordered him jailed for 20 days.
With reporting by RFE/RL’s Russian Service, Interfax, AP, AFP, and Reuters