Story highlights Alexey Navalny jailed for 15 days, fined for organizing Moscow protest that attracted thousands

Kremlin condemns country-wide demonstrations and suggests children were paid to attend

(CNN) Defiant Russian opposition leader Alexey Navalny has been jailed for 15 days over his role in a mass anti-corruption protest in Moscow.

Navalny, who was arrested at Sunday's demonstration, was sentenced by a court in Moscow on Monday afternoon for disobeying a police officer.

The verdict was tweeted by his press secretary.

He was also fined 20,000 roubles (around $350) after being convicted of organizing the march and disturbing public peace.

Navalny struck a defiant note during the hearing.

Navalny, who rose to prominence during the large-scale anti-government protests in Russia in 2011, plans to run for the Russian presidency in 2018.

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