Definition: In this task, you need to generate an appropriate title for the given summary of some paragraph. The generated title must be short and should include the main topic of the given text. Your summary should be less than 20 words long.
Input: Russia's main opposition leader, Alexei Navalny, has been arrested at an anti-corruption protest he organised in the capital, Moscow.

Russia protests: Opposition leader Navalny and hundreds of others held