agitator:
(plural: ‘agitators‘; pronunciation: the letter ‘g’ is said with a ‘dg’ sound as in “judge”)

agitators at a demostration
a person who excites and influences other people’s feelings or line of thinking especially with logical or convincing arguments towards political or social change in a society, country, etc., (which usually results in people turning violent — using force and destructive methods to gain that desired change);
a trouble maker; a revolutionary,

angry agitators burning vehicles
A famous social worker from our state was accused of being an agitator and was house-arrested.
When there are serious protests and marches against a government, the government sends its own agitators into action and they create confusion and disorder in the public, which finally results in people forgetting why they have started the agitation in the first place!
