The weeds have 'run riot' over our poor garden. [=the weeds in our garden have grown quickly and have taken over the garden]
The field was a 'riot' of wildflowers. [=the field was filled with many kinds of wildflowers]
The news about the election caused/started/sparked a 'riot' in the city.
(..) Please, have a seat. Are you aware of what's happened? When you fired your arrow at the force field you electrified the nation. There have been riots and uprisings and strikes in seven districts. We believe that if we keep this energy going we can unify the districts against the Capitol. (..)2014 The Hunger Games: Mockingjay - Part 1