Behind the Riots - a Newsround Special
August 2011, and some of England's biggest cities see four days of violence and looting.
They were scenes that hadn't been seen for a long, long time - and shocked people around the country.
Now, with the cities much calmer, the question is - why did this happen?
Sonali looks into just what happened and what might have caused them, as she goes 'Behind the Riots'.